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AGRICULTURE 


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iT* 


UNIVERSITY  OF  ILLINOIS 
AGRICULTUE/L  EXPERIMENT  station 


SOIL  EFFORT 
1-10 


1911-15 


URBANA, ILLINOIS 


i>6  <■> 


■Vur,  \ - \ 0 CONT^TTS 


1 Clay  county  soils 

2 Moultrie  county  soils 

3 Hardin  county  soils 

4 Sangamon  county  soils 
6 La  Salle  county  soils 

6 Knox  county  soils 

7 McDonough  county  soils 

8 Bond  county  soils 

9 Lake  county  soils 

10  McLean  county  soils 


UNIVERSITY  OF  ILLINOIS 
agriculture  library 


,A 


•Il>o7G2 


I 


UNIV^S'TY  OF  ILLINOIS 
, LIBRARY 


UNIVERSITY  OF  ILLINOIS 

Agricultural  Experiment  Station 

SOIL  REPORT  NO.  1 

CLAY  COUNTY  SOILS 


By  CYRIL,  G.  HOPKINS,  J.  G.  MOSIER, 
J.  H.  PETTIT,  and  J.  E.  READHIMER 


URBANA,  ILLINOIS,  MARCH,  1911 


State  Advisory  Committee  on  Soil  Investigations 

Ralph  Allen,  Delavan 

F.  I.  Mann,  Gilman 

A.  N.  Abbott,  Morrison 

J.  P.  Mason,  Elgin 

E.  W.  Burroughs,  Edwardsville 

Agricultural  Experiment  Station  Staff  on  Soil  Investigations 
Eugene  Davenport,  Director 

Cyril  G.  Hopkins,  Chief  in  Agronomy  and  Chemistry 
Soil  Survey — 

J.  G.  Mosier,  Assistant  Chief 
A.  F.  Gustafson,  Assistant 
C.  C.  Logan,  Assistant 
S.  V.  Holt,  Assistant 
H.  W.  Stewart,  Assistant 
H.  C.  Wheeler,  Assistant 

Soil  Analysis — 

J.  H.  Pettit,  Assistant  Chief 
E.  VanAlstine,  Assistant 
J.  P.  Aumer,  Assistant 
Gertrude  Niederman,  Assistant 
W.  H.  Sachs,  Assistant 
Frances  D.  Abbott,  Assistant 
W.  R.  Leighty,  Assistant 

Soil  Experiment  Fields — 

J.  E.  Readhimer,  Superintendent 
Wm.  G.  Eckhardt,  Assistant 
O.  S.  Fisher,  Assistant 
J.  E.  Whitchurch,  Assistant 
E.  E,  Hoskins,  Assistant 


V'- 

UNIVERSITY  OF  ILLINOIS 
BdRICULTURE  LIBRARY 


CLAY  COUNTY  SOILS 

By  CYRIL  G.  HOPKINS,  J.  G.  MOSIER,  J.  H.  PETTIT  and  J.  E.  READHIMER 


Introduction 

The  Illinois  County  Soil  Reports,  beginning  with  Report  No.  i,  “Clay 
County  Soils,”  constitute  a series  of  publications  separate  and  distinct  from 
the  bulletins  and  circulars  of  the  Experiment  Station.  At  least  three  of 
these  county  reports  will  be  sent  to  the  Station’s  entire  mailing  list.  These 
three  are  the  reports  of  Clay  County,  representing  the  common  soils  of  south- 
ern Illinois;  Moultrie  County,  representing  the  common  corn  belt  soils;  and 
Hardin  County,  representing  the  unglaciated  Ozark  Hills  region.  As  a rule 
the  other  soil  reports  will  be  sent  only  to  the  residents  of  the  respective  coun- 
ties, and  to  others  upon  request.  This  plan  requires  that  each  county  report 
shall  be  as  complete  as  practicable,  and  consequently  this  general  discussion 
of  soil  principles,  which  appears  as  an  introduction  in  the  Clay  County  Re- 
port, may  be  found  with  any  necessary  modifications  as  an  appendix  to 
every  other  county  report. 

A study  of  the  soil  map  and  the  tabular  statements  concerning  crop  re- 
quirements, the  plant  food  content  of  the  different  soil  types,  and  the  actual 
results  secured  from  definite  field  trials  with  different  methods  or  systems 
ot  soil  improvement,  and  a careful  study  of  the  discussion  of  general  prin- 
ciples and  of  the  descriptions  of  individual  soil  types  will  furnish  the  most 
necessary  and  useful  information  for  the  practical  improvement  and  perma- 
nent preservation  of  the  productive  power  of  every  kind  of  soil  on  every 
farm  in  the  county. 

More  complete  information  concerning  the  most  extensive  and  important 
soil  types  in  the  great  soil  areas  in  all  parts  of  Illinois  is  contained  in  Bulle- 
tin No.  123,  “The  Fertility  in  Illinois  Soils,”  which  contains  a colored  gen- 
eral survey  soil  map  of  the  entire  state. 

Other  publications  of  general  interest  are : 

Bulletin  No.  76,  “Alfalfa  on  Illinois  Soils.” 

Bulletin  No.  94,  “Nitrogen  Bacteria  and  Legumes.” 

Bulletin  No.  99,  “Soil  Treatment  for  the  Lower  Illinois  Glaciation.” 

Bulletin  No.  1 15,  “Soil  Improvement  for  the  Worn  Hill  Lands  of  Illinois.” 

Bulletin  No.  125,  “Thirty  Years  of  Crop  Rotation  on  the  Common  Prairie  Lands  of 
Illinois.” 

Circular  No.  no,  “Ground  Limestone  for  Acid  Soils.” 

Circular  No.  127,  “Shall  we  use  Natural  Rock  Phosphate  or  Manufactured  Acid  Phos- 
phate for  the  Permanent  Improvement  of  Illinois  Soils?” 

Circular  No.  129,  “The  Use  of  Commercial  Fertilizers.” 

Circular  No.  149,  “Some  Results  of  Scientific  Soil  Treatment”  and  “Methods  and  Re- 
sults of  Ten  Years’  Soil  Investigation  in  Illinois.” 

NOTE. — Information  as  to  where  to  obtain  limestone,  phosphate,  bone  meal  and  oo- 
tasstum  salts,  methods  of  application,  etc.,  will  also  be  found  in  Circular  no. 


2 


Soil  Report  No.  i 


[March, 


Soil  Survey  Methods 

The  detail  soil  survey  of  a county  consists  essentially  of  indicating  on 
a map  the  location  and  extent  of  the  different  soil  types;  and,  since  the 
value  of  the  survey  depends  upon  its  accuracy,  every  reasonable  means  is 
employed  to  make  it  trustworthy.  To  accomplish,  this  object  three  things  are 
essential:  first,  careful,  well-trained  men  to  do  the  work;  second,  an  ac- 
curate base  map  upon  which  to  show  the  results  of  their  work;  and,  third, 
the  means  necessary  to  enable  the  men  to  place  the  soil  type  boundaries, 
streams,  etc.,  accurately  upon  the  map. 

The  men  selected  for  the  work  must  be  able  to  keep  their  location  exactly 
and  to  recognize  the  different  soil  types,  with  their  principal  varieties  and  lim- 
its, and  they  must  show  these  upon  the  maps  correctly.  A definite  system  is 
employed  in  checking  up  this  work.  As  an  illustration,  one  soil  expert  will 
survey  and  map  a strip  80  rods  or  160  rods  wide  and  any  convenient  length, 
while  his  associate  will  work  independently  on  another  strip  adjoining  this 
area,  and,  if  the  work  is  correctly  done,  the  soil  type  boundaries  will  match 
up  on  the  line  between  the  two  strips. 

An  accurate  base  map  for  field  use  is  absolutely  necessary  for  soil  map- 
ping. The  base  mapc  are  made  on  a scale  of  one  inch  to  the  mile.  The 
official  data  of  the  original  or  subsequent  land  survey  are  used  as  a basis 
in  the  construction  of  these  maps,  while  the  most  trustworthy  county  map 
available  is  used  in  locating  temporarily  the  streams,  roads,  and  railroads. 
Since  the  best  of  these  published  maps  have  some  inaccuracies,  the  location 
of  every  road,  stream,  and  railroad  must  be  verified  by  the  soil  surveyors, 
and  corrected  if  wrongly  located.  In  order  to  make  these  verifications  and 
corrections,  each  survey  party  is  provided  with  an  odometer  for  measuring 
distances,  and  a plane  table  for  determining  the  directions  of  roads,  rail- 
roads, etc. 

Each  surveyor  is  provided  with  a base  map  of  the  proper  scale,  which  is 
carried  with  him  in  the  field,  and  the  soil  type  boundaries,  additional  streams, 
and  necessary  corrections  are  placed  with  proper  locations  upon  the  map  while 
the  mapper  is  on  the  area.  Each  section,  or  square  mile,  is  divided  into 
40-acre  plots  on  the  map  and  the  surveyor  must  inspect  every  ten  acres  and 
determine  the  type  or  types  of  soil  composing  it.  The  different  types  are 
indicated  on  the  map  by  different  colors,  pencils  being  carried  in  the  field 
for  this  purpose. 

A small  auger  40  inches  long  forms  for  each  man  an  invaluable  tool  with 
which  he  can  quickly  secure  samples  of  the  different  strata  for  inspection. 
An  extension  for  making  the  auger  80  inches  long  is  taken  by  each  party, 
so  that  any  peculiarity  of  the  deeper  subsoil  layers  may  be  studied.  Each 
man  carries  a compass  to  aid  in  keeping  directions.'  Distances  along  roads 
are  measured  by  an  odometer  attached  to  the  axle  of  the  vehicle,  while  dis- 
tances in  . the  field  off  the  roads  are  determined  by  pacing,  an  art  in  which 
the  ‘men  become  expert  by  practice.  The  soil  boundaries  can  thus  be  lo- 
cated with  as  high  a degree  of  accuracy  as  can  be  indicated  by  pencil  on  tin 
scale  of  one  inch  to  the  mile. 


Clay  County 


3 


1911] 


Soil  Characteristics 


The  unit  in  the  soil  survey  is  the  soil  type,  and  each  type  possesses 
more  or  less  definite  characteristics.  The  line  of  separation  between  ad- 
joining types  is  usually  distinct,  but  sometimes  one  type  will  grade  into 
another  so  gradually  that  it  is  very  difficult  to  draw  the  line  between  them. 
In  such  exceptional  cases,  some  slight  variation  in  the  location  of  soil  type 
boundaries  is  unavoidable. 

Several  factors  must  be  taken  into  account  in  establishing  soil  types. 
These  are  (1)  the  geological  origin  of  the  soil,  whether  residual,  glacial, 
loessial,  alluvial,  colluvial,  or  cumulose;  (2)  the  topography,  or  lay  of  the 
land;  (3)  the  structure,  or  the  depth  and  character  of  the  surface,  subsur- 
face, and  subsoil;  (4)  the  physical  or  mechanical  composition  of  the  differ- 
ent strata  composing  the  soil,  as  the  percentages  of  gravel,  sand,  silt,  clay, 
and  organic  matter  which  they  contain;  (5)  the  texture,  or  porosity,  granu- 
lation, friability,  plasticity,  etc.;  (6)  the  color  of  the  strata;  (7)  the  natural 
drainage;  (8)  agricultural  value,  based  upon  its  natural  productiveness; 
(9)  native  vegetation;  (10)  the  ultimate  chemical  composition  and  re- 
action. 

The  common  soil  constituents  are  indicated  in  the  following  outline: 


Constituents  of  Soils 


Soil 

Constituents 


Organic 

Matter 


Inorganic 

Matter 


t Comprising  undecomposed  and  partially  decayed 
( vegetable  material 


Clay  001  mm.*  and  less 

Silt  001  mm.  to  .03  mm. 

Sand  03  mm.  to  1.  mm. 

Gravel  1.  mm.  to  32  mm. 

Stones  32.  mm.  and  over. 


*25  millimeters  equal  1 inch. 

Further  discussion  of  these  constituents  is  given  in  Circular  82. 


Groups  oe  Soil  Types 

The  following  gives  the  different  general  groups  of  soils : 

Peats — Consisting  of  35  percent  or  more  of  organic  matter,  sometimes 
mixed  with  more  or  less  sand  or  silt. 

Peaty  loams — 15  to  35  percent  of  organic  matter  mixed  with  much  sand 
and  silt  and  a little  clay. 

Mucks — 15  to  35  percent  of  partly  decomposed  organic  matter  mixed 
with  much  clay  and  some  silt. 

Clays — Soils  with  more  than  25  percent  of  clay,  usually  mixed  with  much 

silt. 

Clay  loams — Soils  with  from  15  to  25  percent  of  clay,  usually  mixed 
with  much  silt  and  some  sand. 

Silt  loams — Soils  with  more  than  50  percent  of  silt  and  less  than  15 
percent  of  clay,  mixed  with  some  sand. 


Soil  Report  No. 


[March, 


Loams — Soils  with  from  30  to  50  percent  of  sand  mixed  with  much 
silt  and  a little  clay. 

Sandy  loams — Soils  with  from  50  to  75  percent  of  sand. 

Fine  sandy  loams — Soils  with  from  50  to  75  percent  of  fine  sand  mixed 
with  much  silt  and  little  clay. 

Sands — Soils  with  more  than  75  percent  of  sand. 

Gravelly  loams — Soils  with  25  to  50  percent  gravel  with  much  sand  and 
some  silt. 

Gravels — Soils  with  more  than  50  percent  of  gravel. 

Stony  loams — Soils  containing  a considerable  number  of  stones  over  one 
inch  in  diameter. 

Rock  outcrop — Usually  ledges  of  rock  having  no  agricultural  value. 

More  or  less  organic  matter  is  found  in  nearly  all  of  the  above  classes. 

Supply  and  Liberation  of  Plant  Food 

The  productive  capacity  of  land  in  humid  sections  depends  almost  wholly 
upon  the  power  of  the  soil  to  feed  the  crop;  and  this,  in  turn,  depends  both 
upon  the  stock  of  plant  food  contained  in  the  soil  and  upon  the  rate  at 
which  this  is  liberated,  or  rendered  soluble  and  available  for  use  in  plant 
growth.  Protection  from  weeds,  insects,  and  fungous  diseases  tho  exceed- 
ingly important  is  not  a positive,  but  a negative  factor  in  crop  production. 

The  chemical  analysis  of  the  soil  gives  the  invoice  of  fertility  actually 
present  in  the  soil  strata  sampled  and  analyzed,  but  the  rate  of  liberation  is 
governed  by  many  factors,  some  of  which  may  be  controlled  by  the  farmer, 
while  others  are  largely  beyond  his  control.  Chief  among  the  important 
controllable  factors  which  influence  the  liberation  of  plant  food  are  lime- 
stone and  decaying  organic  matter,  which  may  be  added  to  the  soil  by  direct 
application  of  ground  limestone  and  farm  manure.  Organic  matter  may 
also  be  supplied  by  green  manure  crops  and  crop  residues,  such  as  clover, 
cowpeas,  straw,  and  cornstalks.  The  rate  of  decay  of  organic  matter  de- 
pends largely  upon  its  age  and  origin,  and  it  may  be  hastened  by  tillage.  The 
chemical  analysis  shows  correctly  the  total  organic  carbon,  which  repre- 
sents, as  a rule,  but  little  more  than  half  the  organic  matter;  so  that  20,000 
pounds  of  organic  carbon  in  the  plowed  soil  of  an  acre  corresponds  to 
nearly  20  tons  of  organic  matter.  But  this  organic  matter  consists  largely 
of  the  old  organic  residues  that  have  accumulated  during  the  past  centuries 
because  they  were  resistant  to  decay,  and  2 tons  of  clover  or  cowpeas 
plowed  under  may  have  greater  power  to  liberate  plant  food  than  the  20 
tons  of  old  inactive  organic  matter.  The  recent  history  of  the  individual 
farm  or  field  must  be  depended  upon  for  information  concerning  recent  ad- 
ditions of  active  organic  matter,  whether  in  applications  of  farm  manure, 
in  legume  crops,  or  in  grass  root  sods  of  old  pastures. 

Probably  no  agricultural  fact  is  more  generally  known  by  farmers  and 
landowners  than  that  soils  differ  in  productive  power.  Even  though  plowed 
alike  and  at  the  same  time,  prepared  the  same  way,  planted  the  same  day 


Clay  County 


s 


1911] 

with  the  same  kind  of  seed,  and  cultivated  alike,  watered  by  the  same  rains 
and  warmed  by  the  same  sun,  nevertheless  the  best  acre  may  produce  twice 
as  large  a crop  as  the  poorest  acre  on  the  same  farm,  if  not,  indeed,  in  the 
same  field ; and  the  fact  should  be  repeated  and  emphasized  that  the  produc- 
tive power  of  the  land  depends  primarily  upon  the  stock  of  plant  food  con- 
tained in  the  soil  and  upon  the  rate  at  which  it  is  liberated,  just  as  the  suc- 
cess of  the  merchant  depends  primarily  upon  his  stock  of  goods  and  the 
rapidity  of  sales.  In  both  cases  the  stock  of  any  commodity  must  be  increased 
or  renewed  whenever  the  supply  of  such  commodity  becomes  so  depleted  as 
to  limit  the  success  of  the  business,  whether  on  the  farm  or  in  the  store. 

As  the  organic  matter  decays,  certain  decomposition  products  are  formed, 
including  much  carbonic  acid,  seme  nitric  acid,  and  various  organic  acids, 
and  these  have  power  to  act  upon  the  soil  and  dissolve  the  essential  mineral 
plant  foods,  thus  furnishing  nitrates,  phosphates,  and  other  salts  of  potas- 
sium, magnesium,  calcium,  etc.,  for  the  use  of  the  growing  crop. 

As  already  explained,  fresh  organic  matter  decomposes  much  more  rap- 
idly than  the  old  humus,  which  represents  the  organic  residues  most  resistant 
to  decay  and  which  consequently  have  accumulated  in  the  soil  during  the 
past  centuries.  The  decay  of  this  old  humus  can  be  hastened  both  by  tillage, 
which  maintains  a porous  condition  and  thus  permits  the  oxygen  of  the 
air  to  enter  the  soil  more  freely  and  to  effect  the  more  rapid  decomposition 
or  oxidation  of  the  organic  matter,  and  also  by  incorporating  with  the  old 
resistant  residues  some  fresh  organic  matter,  such  as  farm  manure,  clover 
roots,  etc.,  which  decay  rapidly  and  which  thus  furnish  or  liberate  organic 
matter  and  inorganic  food  for  bacteria,  which,  under  such  favorable  con- 
ditions appear  to  have  power  to  attack  and  decompose  the  old  humus.  It  is 
probably  for  this  reason  that  peat,  a very  inactive  and  inefficient  fertilizer 
when  used  by  itself,  becomes  much  more  effective  when  incorporated  with  fresh 
farm  manure,  so  that  when  used  together,  two  tons  of  the  mixture  may  be 
worth  as  much  as  two  tons  of  manure,  but  if  applied  separately,  the  peat 
has  little  value.  Bacterial  action  is  also  promoted  by  the  presence  of  lime- 
stone. 

It  should  be  kept  in  mind  that  crops  are  not  made  out  of  nothing.  They 
are  composed  of  ten  different  elements  of  plant  food,  every  one  of  which  is 
absolutely  essential  for  the  growth  and  formation  of  every  agricultural  plant. 
Of  these  ten  elements  of  plant  food,  only  two  (carbon  and  oxygen)  are 
secured  from  the  air  by  all  plants,  only  one  (hydrogen)  from  water,  and 
seven  from  the  soil.  Nitrogen,  one  of  these  seven  elements  secured  from  the 
soil  by  all  plants,  may  also  be  secured  from  the  air  by  one  class  of  plants 
(legumes),  in  case  the  amount  liberated  from  the  soil  is  insufficient;  but 
even  these  plants  (which  include  only  the  clovers,  peas,  beans,  and  vetches 
among  our  common  agricultural  plants)  secure  six  elements  from  the  soil 
(phosphorus,  potassium,  magnesium,  calcium,  iron,  and  sulfur),  and  also 
utilize  the  soil  nitrogen  so  far  as  it  becomes  soluble  and  available  during 
their  period  of  growth. 

Plants  are  made  of  these  plant-food  elements  in  just  the  same  sense  that 
a building  is  made  of  wood  and  iron,  brick,  stone,  and  mortar.  Without 


6 


Soil  Report  No. 


[March, 


materials,  nothing  material  can  be  made.  The  normal  temperature,  sunshine, 
rainfall,  and  length  of  season  in  southern  Illinois  are  sufficient  to  produce 
50  bushels  of  wheat  per  acre,  100  bushels  of  corn,  100  bushels  of  oats,  and 
4 tons  of  clover  hay ; and,  where  the  land  is  properly  drained  and  properly 
tilled,  such  crops  would  frequently  be  secured  if  the  plant  foods  were  pres- 
ent in  sufficient  amount  and- liberated  at  a sufficiently  rapid  rate  to  meet  the 
absolute  needs  of  the  crops. 


Crop  Requirements 

The  accompanying  table  shows  the  requirements  of  such  crops  for  the 
five  most  important  plant  food  elements  which  the  soil  must  furnish.  (Iron 
and  sulfur  are  supplied  normally  in  sufficient  abundance  compared  with  the 
amounts  needed  by  plants,  so  that  they  are  not  known  ever  to  limit  the  yield 
of  crops)  : 


Table  1 — Plant  Pood  in  Wheat,  Corn,  Oats,  and  Clover 


Produce 

Nitro- 

Phos- 

Potas- 

Magne- 

Cal- 

gen, 

phorus, 

sium, 

sium, 

cium, 

Kind 

Amount 

pounds 

pounds 

pounds 

pounds 

pounds 

Wheat,  grain 

50  bu. 

71 

12 

13 

4 

1 

Wheat  straw 

lYz  tons 

25 

4 

45 

4 

10 

Corn,  grain 

100  bu. 

100 

17 

19 

7 

1 

Corn  stover 

3 tons 

48 

6 

52 

10 

21 

Corn  cobs 

Yz  ton 

2 

2 

Oats,  grain 

100  bu. 

66 

.11 

16 

4 

2 

Oat  straw 

2 Yz  tons 

31 

5 

52 

7 

IS 

Clover  seed 

4 bu. 

7 

2 

3 

1 

1 

Clover  hay 

4 tons 

160 

20 

120 

31 

117 

Total  in  grain  and  seed 

244* 

42 

51 

16 

4 

Total  in  four  crops  . . . . 

510* 

77 

322 

68 

168 

To  be  sure,  these  are  large  yields,  but  shall  we  try  to  make  possible  the 
production  of  yields  only  half  or  a quarter  as  large  as  these,  or  shall  we 
set  as  our  ideal  this  higher  mark,  and  then  approach  it  as  nearly  as  pos- 
sible with  profit?  Among  the  four  crops,  corn  is  the  largest,  with  a total 
yield  of  more  than  six  tons  per  acre;  and  yet  the  100-bushel  crop  of  corn. is 
often  produced  on  rich  pieces  of  land  in  good  seasons.  In  very  practical 
and  profitable  systems  of  farming,  the  Illinois  Experiment  Station  has  pro- 
duced, as  an  average  of  the  six  years,  1905  to  1910,  a yield  of  87  bushels 
of  corn  per  acre  in  grain  fanning  (with  limestone  and  phosphorus  applied, 
and  with  crop  residues  and  legume  crops  turned  under),  and  90  bushels  per 
acre  in  live-stock  farming  (with  limestone,  phosphorus,  and  manure). 

On  the  Edgewood  Experiment  Field,  less  than  five  miles  from  the  north 
line  of  Clay  County,  and  on  the  common  prairie  land  of  southern  Illinois, 
yields  have  been  obtained  as  high  as  91  bushels  per  acre  of  corn,  74  bushels 
of  oats,  and  2.91  tons  of  air-dry  clover  hay,  in  the  first  cutting,  and  prob- 
ably more  than  1 ton  in  the  second  crop,  which,  however,  was  plowed  under 
without  weighing. 


*These  amounts  include  the  nitrogen  contained  in  the  clover  seed  or  hay,  which, 
however,  may  be  secured  from  the  air. 


EFFINGHAM  COUNTY 


HivLaAVjI 


AiIiNi  IOO  H m z 


SOIL  SURVEY  MAP  OF  CLAY  COUNTY 
UNIVERSITY  OF  ILLINOIS  AGRICULTURAL  EXPERIMENT  STATION 


Clay  County 


7 


1911] 


THE  FERTILITY  IN  CLAY  COUNTY  SOILS 
Origin  of  Soil  Material 

Clay  County  was  covered  by  the  Illinoisan  ice  sheet,  which  generally 
leveled  down  hills  and  filled  valleys,  and  left  that  part  of  the  state  as  a 
broad  level  expanse  broken  only  by  a few  morainal  or  preglacial  ridges, 
remnants  of  which  now  form  our  ridge  soils.  The  ice  sheet  in  its  move- 
ment southward  carried  large  amounts  of  earthy  material  of  various  sizes, 
including  boulders,  gravel,  sand,  silt  and  clay,  which  were  deposited  when 
the  ice  melted,  forming  what  is  known  as  till,  boulder  clay,  or  glacial  drift, 
which  may  be  recognized  readily  by  its  composite  character. 

After  the  ice  sheet  melted,  the  surface  of  the  glacial  drift  was  slowly 
and  gradually  changed  into  a soil  which  varied  somewhat  as  soils  do  now. 

At  the  close  of  the  Iowan  glaciation,  which  followed  the  Illinoisan,  the 
entire  state  was  covered  with  a wind-blown  dust,  known  as  loess,  which 
was  deposited  somewhat  uniformly  over  this  region  to  a depth  of  from  4 
to  10  feet,  burying  the  old  soil  completely.  A new  soil  was  formed  from  this 
fine  material  by  the  subsequent  weathering  and  the  accumulation  of  organic 
matter,  which  has  been  modified  to  form  the  present  soils.  The  old  buried 
soil,  known  as  the  Sangamon  soil,  is  sometimes  exposed  along  streams  or 
roadsides,  occasionally  as  a dark  heavy  stratum  two  or  three  feet  thick,  while 
in  other  places  it  is  represented  only  by  a weathered  surface  of  the  glacial 
drift. 

Table  2. — Son,  Types  of  Clay  County 


Soil  type 
No. 

Names 

Area  in 
acres 

Percent 
of  total 

330 

(a)  Upland  Prairie  Soils  (Page  22) 

Gray  silt  loam  on  tight  clay 

110,720 

37.000 

328 

Brown-gray  silt  loam  on  tight  clay 

960 

.330 

329 

Drab  silt  loam  

14,400 

4.800 

326.1 

Brown  silt  loam  on  clay 

824 

.270 

331 

Deep  gray  silt  loam 

1,760 

.590 

332 

(b)  Upland  Timber  Soils  (Page  26) 

Tight  gray  silt  loam  on  tight  clay 

51,200 

17.130 

332.1 

White  silt  loam  on  tight  clay 

224 

.073 

334 

Yellow-gray  silt  loam 

21,240 

41,760 

7.090 

335 

Y ellow  silt  loam  

14.000 

235 

(c)  Ridge  Soils  (Page  29) 

Y ellow  silt  loam 

2,560 

.854 

233 

Gray- red  silt  loam  on  tight  clay , 

9,180 

3.000 

1331 

(d)  Swamp  and  Bottom  land  Soils  (Page  30) 
Deep  gray  silt  loam 

31,680 

10.580 

1361 

Mixed  sandy  loam 

12,800 

4.270 

1315 

Drab  clay  

25 

.008 

1301 

Deep  peat  

15 

.005 

'T'n+a  Is 

299,348 

100.000 

The  data  in  Table  3 represent  the  total  amounts  of  plant  food  found  in  2 
million*  pounds  of  the  surface  soil,  which  corresponds  to  an  acre  of  soil  about 
62/z  inches  deep,  including  at  least  as  much  soil  as  is  ordinarily  turned  with  the 
plow,  and  representing  that  part  of  the  soil  with  which  we  incorporate  the 
farm  manure,  limestone,  phosphate,  or  other  fertilizer  applied  in  soil  im- 
provement. This  is  the  soil  stratum  upon  which  we  must  depend  in  large 

*The  amounts  are  for  only  1 million  pounds  of  the  peat  soil  because  its  specific 
gravity  is  only  one-half  that  of  normal  soils. 


Soil  Report  No.  i 


[March, 


part  to  furnish  the  necessary  plant  food  for  the  production  of  the  crops 
grown. 

In  Table  3 is  recorded  the  invoice  of  the  plowed  soil,  showing  the  total 
amounts  of  these  five  elements  of  plant  food  contained  in  each  of  the  differ- 
ent types  of  soil  in  Clay  County.  (For  more  details  see  Bulletin  123.) 


Table  3 — Fertility  in  the  Soils  of  Clay  County,  Illinois 
Average  pounds  per  acre  in  2 million  pounds  of  surface  soil  (about  6%  inches) 


Soil 

Total 

Total 

Total 

Total 

Total 

Total 

Lime- 

Lime- 

type 

Soil  type 

organic 

nitro- 

phos- 

potas- 

magne- 

calci- 

stone 

stone 

No. 

carbon 

gen 

phorus 

sium 

sium 

um 

present 

required 

Upland  Prairie  Soils 


330 

Gray  silt  loam 

on  tight  clay 

26970 

2790 

750 

24830 

4690 

3420 

1130 

328 

Brown-gray 

silt  loam  on 
tight  clay. . . 

30600 

3020 

1020 

25760 

5780 

4020 

160 

329 

Drab  silt  loam 

23640 

2560 

630 

25110 

4560 

6270 

1520 

326.1 

Brown  silt 

loam  on  clay 

30740 

3320 

700 

24700 

5520 

7720 

1500 

331 

Deep  gray 

silt  loam. . . . 

20800 

2180 

600 

24220 

3000 

4900 

1640 

Upland  Timber  Soils 


332 

Light-gray  silt 

loam  on 
tight  clay. . . 

17810 

1580 

760 

27860 

4310 

4620 

480 

322.1 

White  silt  loam 

on  tight  clay 

16980 

1120 

400 

29380 

4940 

4060 

840 

334 

Yellow-gray 

silt  loam. . . . 

19600 

1650 

550 

30200 

5490 

6920 

40 

335 

Yellow  silt  loam 

16990 

1540 

510 

31430 

3800 

3000 

2250 

Ridge  Soils 


235 

233 

Y ellow  silt 

loam 

Gray-red  silt 
loam  on 
tight  clay. . . 

41970 

27380 

3890 

2720 

820 

760 

29500 

27300 

8140 

5200 

6040 

4320 

140 

1040 

Swamp  and  Bottom-land 

Soils 

1331 

Deep  gray 

silt  loam .... 

31470 

2910 

1350 

34740 

7700 

7580 

100 

1361 

Mixed  sandy 

loam 

26950 

2700 

750 

31410 

6350 

7950 

80 

1315 

Drab  clay 

43960 

4180 

1040 

35300 

10920 

8160 

40 

1301 

Deep  peat*  . . . 

297660 

16790 

930 

6190 

7240 

107900 

224680 

The  importance  of  maintaining  a rich  surface  soil  cannot  be  too  strongly 
emphasized.  It  is  well  illustrated  by  data  from  the  Rothamsted  Experi- 
ment Station,  the  oldest  in  the  world.  Thus  on  Broadbalk  field,  where 
wheat  has  been  grown  since  1844,  the  average  yields  for  the  ten  years, 
1892  to  1901  were  12.3  bushels  per  acre  on  plot  3 (unfertilized)  and  31.8 
bushels  on  plot  7 (well  fertilized),  but  the  amounts  of  both  nitrogen  and 
phosphorus  in  the  subsoil  (9  to  27  inches)  were  distinctly  greater  in  plot 
3 than  in  plot  7,  thus  showing  that  the  higher  yields  from  plot  7 were  due 
to  the  fact  that  the  plowed  soil  had  been  enriched.  In  1893,  plot  7 contained 
per  acre  in  the  surface  soil  (o  to  9 inches)  about  600  pounds  more  nitro- 
gen and  900  pounds  more  phosphorus  than  plot  3.  Even  a rich  subsoil  has 
little  value  if  it  lies  beneath  a worn-out  surface. 

* Amounts  reported  are  from  1 million  pounds  of  peat  soil. 


EFFINGHAM  R.  7 E < ol-NTY 


RICHLAND  l-'^z 


! 


SOIL  SURVEY  MAP  OF  CLAY  COUNTY 
UNIVERSITY  OF  ILLINOIS  AGRICULTURAL  EXPERIMENT  STATION 


Clay  County 


9 


1911 1 


By  easy  computation  it  will  be  found  that  not  one  of  the  prairie  soils 
of  Clay  County  contains  enough  total  nitrogen  in  the  plowed  soil  for  the  pro- 
duction of  maximum  crops  for  ten  rotations;  while  the  upland  timber  soils 
contain  as  an  average  only  about  half  as  much  nitrogen  as  the  prairie 
land. 

Practically  the  same  condition  obtains  with  respect  to  phosphorus,  only 
two  of  the  eleven  upland  soils  containing  as  much  of  that  element  as  would 
be  required  for  ten  crop  rotations  if  such  crop  yields  were  secured  as  sug- 
gested in  Table  1 ; and  in  case  of  the  cereals  it  will  be  seen  that  about 
three-fourths  of  the  phosphorus  taken  from  the  soil  is  deposited  in  the 
grain,  while  only  one-fourth  remains  in  the  straw  or  stalks.  If  only  the 
grain  and  seed  were  sold  from  the  farm  the  total  supply  of  phosphorus  in 
the  plowed  soil  is  no  more  than  would  need  to  leave  the  farm  during  the  full 
time  of  one  life  (70  years). 

On  the  other  hand,  the  potassium  is  sufficient  for  2000  years,  if  only 
the  grain  is  sold,  or  for  300  years  if  the  total  crops  are  removed;  and  the 
corresponding  figures  are  about  1200  and  300  years  for  magnesium,  and 
about  3000  and  100  years  for  calcium. 

Thus  when  measured  by  the  actual  crop  requirements  for  plant  food 
magnesium  and  calcium  are  more  limited  than  potassium.  But  with  these 
elements  we  must  also  consider  the  loss  by  leaching.  As  an  average  of 
90  analyses*  of  Illinois  well-waters  drawn  chiefly  from  glacial  sands,  grav- 
els, or  till,  3 million  pounds  of  water  (about  the  average  annual  drainage 
per  acre- for  Illinois)  contained  11  pounds  of  potassium,  130  of  magnesium, 
and  330  of  calcium.  These  figures  are  very  significant,  and  it  may  be 
stated  that  if  the  plowed  soil  is  well  supplied  with  the  carbonates  of  mag- 
nesium and  calcium,  then  a very  considerable  proportion  of  these  amounts 
will  be  leached  from  that  stratum.  Thus  the  loss  of  calcium  from  the 
plowed  soil  of  an  acre  at  Rothamsted,  England,  where  the  soil  contains 
plenty  of  limestone,  has  averaged  more  than  300  pounds  a year  as  de- 
termined by  analyzing  the  soil  in  1865  and  again  in  1905. 

It  is  of  interest  to  note  that  thirty  crops  of  clover  of  4 tons  each  would 
require  3510  pounds  of  calcium,  while  the  most  common  prairie  land  (gray 
silt  loam  on  tight  clay)  contains  only  3420  pounds  of  total  calcium  in  the 
plowed  soil  of  an  acre. 

These  general  statements  relating  to  the  total  quantities  of  plant  food 
in  the  plowed  soil  certainly  emphasize  the  fact  that  the  supplies  of  some  of 
these  necessary  elements  of  fertility  are  extremely  limited  when  measured 
by  the  need-s  of  large  crop  yields  for  even  one  or  two  generations  of  people. 
We  must  also  consider,  however,  the  question  of  the  rate  at  which  these 
plant  food  elements  may  be  liberated  and  thus  m*ide  available  for  plant 
growth. 

Methods  of  Liberating  Plant  Food 

Limestone  and  decaying  organic  matter  are  the  principal  materials  the 
farmer  can  utilize  most  profitably  to  bring  about  the  liberation  of  plant  food. 

The  limestone  corrects  the  acidity  of  the  soil  and  thus  encourages  the 
development  not  only  of  the  nitrogen-gathering  bacteria  which  live  in  the 
nodules  on  the  roots  of  clover,  cowpeas,  and  other  legumes,  but  also  of  the 
nitrifying  bacteria  which  have  power  to  transform  the  insoluble  and  un- 
available  organic  nitrogen  into  soluble  and  available  nitrate  nitrogen. 

♦Reported  by  Doctor  Bartow  and  associates,  of  the  Illinois  State  Water  Survey. 


10 


Soil  Report  No.  i 


[March, 


At  the  same  time  the  products  of  this  decomposition. have  power  to  dis- 
solve the  minerals  contained  in  the  soil,  such  as  potassium  and  magnesium, 
and  also  to  dissolve  the  insoluble  phosphate  and  limestone  which  may  be 
applied  in  low-priced  forms. 

Tillage,  or  cultivation,  also  hastens  the  liberation  of  plant  food  by  per- 
mitting the  air  to  enter  the  soil  and  burn  out  the  organic  matter;  but  it 
should  never  be  forgotten  that  tillage  is  wholly  destructive,  that  it  adds  noth- 
ing whatever  to  the  soil,  but  always  leaves  the  soil  poorer.  Tillage  should 
be  practiced  so  far  as  is  necessary  to  prepare  a suitable  seed-bed  for  root 
development  and  also  for  the  purpose  of  killing  weeds,  but  more  than  this 
is  unnecessary  and  unprofitable  in  seasons  of  normal  rainfall ; and  it  is 
much  better  actually  to  enrich  the  soil  by  proper  applications  or  additions, 
including  limestone  and  organic  matter  (both  of  which  have  power  to  im- 
prove the  physical  condition  as  well  as  to  liberate  plant  food)  than  merely 
to  hasten  soil  depletion  by  means  of  excessive  cultivation. 

Permanent  Soie  Improvement 

The  best  and  most  profitable  methods  for  the  permanent  improvement 
of  the  common  soils  of  Clay  County  are  as  follows : 

(1)  Apply  at  least  two  tons  (and  better  five  tons)  per  acre  of  ground 
limestone,  preferably  at  times  magnesian  limestone  (CaC03  MgC03) 
which  contains  both  calcium  and  magnesium,  and  has  slightly  greater 
power  to  correct  soil  acidity,  ton  for  ton,  than  the  ordinary  cal- 
cium limestone  (CaC03).  Afterward  continue  to  apply  about  two 
tons  per  acre  of  ground  limestone  every  four  to  six  years. 

(2)  Adopt  a good  rotation  of  crops,  including  a liberal  use  of  legumes, 
and  increase  the  organic  matter  of  the  soil  either  by  plowing  under 
the  legume  crops  and  other  crop  residues  (straw  and  corn  stalks) 
or  by  using  for  feed  and  bedding  practically  all  of  the  crops  raised 
and  returning  the  manure  to  the  land  with  the  least  possible  loss. 
No  one  can  say  in  advance  what  will  prove  to  be  the  best  rotation 
of  crops,  because  of  variation  in  prices  and  seasons,  but  the  follow- 
ing are  suggested  to  serve  as  models  or  outlines : 

First  year,  corn  (with  some  winter  legume,  such  as  red  clover,  alsike,  sweet 
clover,  or  alfalfa,  or  a mixture,  seeded  on  one-half  of  the  field  at  the  last 
cultivation). 

Second  year,  oats  or  barley  on  one-half  and  cowpeas  or  soybeans  where  the 
winter  catch  crop  is  plowed  down. 

Third  year,  wheat  or  rye  (with  clover  or  clover  and  grass). 

Fourth  year,  (1)  clover,  or  (2)  clover  and  timothy,  or  (3)  clover  and  red  top. 
Fifth  year,  (1)  wheat  and  clover,  or  (2)  timothy  and  clover,  or  (3)  red  top. 
Sixth  year,  (1)  clover,  or  (2)  clover  and  timothy,  or  (3)  red  top. 

In  grain  farming,  with  wheat  grown  the  third  and  fifth  years,  most  of 
the  coarse  products  should  be  returned  to  the  soil,  and  the  clover  may  be 
clipped  and  left  on  the  land  (only  the  clover  seed  being  sold  the  fourth  and 
sixth  years)  ; or  in  live-stock  farming,  the  clover  may  be  reseeded  each 
spring,  if  necessary  to  maintain  the  stand,  and  the  field  used  three  years  for 
timothy  and  clover  pasture  and  meadow  as  desired.  If  red  top  is  seeded 
the  clover  will  usually  make  seed  or  both  hay  and  seed  the  fourth  year,  and 
red-top  seed  may  be  sold  the  fifth  and  sixth  years.  To  avoid  clover  sickness 
it  may  sometimes  be  necessary  to  substitute  red  clover  or  alsike  for  the  other 
in  about  every  third  rotation,  and  to  discontinue  their  use  in  the  catch- 
crop  mixture.  If  the  corn  crop  is  not  too  rank,  cowpeas  or  soybeans  may  also 


Clay  County 


11 


1911] 


be  used  as  a catch-crop  and,  if  necessary  to  avoid  disease,  these  may  well 
alternate  in  successive  rotations. 

For  easy  figuring  it  may  well  be  kept  in:  mind  that  the  following  amounts 
of  nitrogen  are  required  for  the  produce  named : 

1 bushel  of  oats  (grain  and  straw)  requires  1 pound  of  nitrogen. 

1 bushel  of  corn  (grain  and  stalks)  requires  il/2  pounds  of  nitrogen. 

1 bushel  of  wheat  (grain  and  straw)  requires  2 pounds  of  nitrogen. 

1 ton  of  timothy  requires  24  pounds  of  nitrogen. 

1 ton  of  red  top  requires  21  pounds  of  nitrogen. 

1 ton  of  average  manure  contains  10  pounds  of  nitrogen. 

1 ton  of  clover  contains  40  pounds  of  nitrogen. 

1 ton  of  cowpeas  contains  43  pounds  of  nitrogen. 

The  roots  of  clover  contain  about  half  as  much  nitrogen  as  the  tops,  and 
the  roots  of  cowpeas  contain  about  one-tenth  as  much  as  the  tops. 

Soils  of  moderate  productive  power  will  furnish  as  much  nitrogen  to 
clover  (and  more  to  cowpeas)  than  will  be  left  in  the  roots  and  stubble. 
For  grain  crops,  as  wheat,  corn,  and  oats,  about  two-thirds  of  the  nitro- 
gen is  contained  in  the  grain  and  one-third  in  the  straw  or  stalks. 

(3)  On  all  of  the  lands  not  subject  to  overflow  (or  susceptible  to  serious 
erosion  by  surface  washing  or  gullying)  apply  the  element  phos- 
phorus in  considerably  larger  amounts  than  are  required  to  meet 
the  actual  needs  of  the  crops  desired  to  be  produced.  The  abundant 
information  thus  far  secured  shows  positively  that  fine-ground  nat- 
ural rock  phosphate  can^be  used  successfully  and  very  profitably, 
and  clearly  indicates  that  this  material  will  be  the  most  economical 
form  of  phosphorus  to  use  in  all  ordinary  systems  of  permanent, 
profitable  soil  improvement.  The  first  application  may  well  be  one 
ton  per  acre  (at  least  one-half  ton  should  be  used),  and  subse- 
quently about  one-half  ton  per  acre  every  four  to  six  years  should 
be  applied,  at  least  until  the  phosphorus  content  of  the  plowed  soil 
reaches  2000  pounds  per  acre,  which  will  require  a total  application  of 
five  or  six  tons  per  acre  of  raw  phosphate  containing  12 percent  of 
the  element  phosphorus.  Steamed  bone  meal  and  even  acid  phos- 
phate may  be  used  in  emergencies,  but  it  should  always  be  kept  in 
mind  that  phosphorus  delivered  in  southern  Illinois  costs  about  3 
cents  a pound  in  raw  phosphate  (direct  from  the  mine  in  carload 
lots),  more  than  10  cents  a pound  in  steamed  bone  meal,  and  more 
than  12  cents  a pound  in  acid  phosphate,  both  of  which  cost  too 
much  per  ton  to  permit  their  common  purchase  by  farmers  in  carload 
lots,  which  is  not  the  case  with  limestone  or  raw  phosphate. 

Phosphorus  once  applied  to  the  soil  remains  in  it  until  removed  in  crops, 
unless  carried  away  mechanically  by  soil  erosion.  (The  loss  by  leaching 
is  only  about  ix/2  pounds  per  acre  per  annum,  so  that  more  than  150  years 
would  be  required  to  leach  away  the  phosphorus  applied  in  one  ton  of  raw 
phosphate). 

The  phosphate  and  limestone  may  be  applied  at  any  time  during  the 
rotation,  but  a good  method  is  to  apply  the  limestone  after  plowing  and 
work  it  into  the  surface  soil  in  preparing  the  seed  bed  for  wheat,  oats, 
rye,  or  barley,  where  clover  is  to  be  seeded,  while  phosphate  is  best  plowed 
under  with  farm  manure,  clover,  or  other  green  manures,  which  serve  to 
liberate  the  phosphorus. 

(4)  Until  the  supply  of  decaying  organic  matter  has  been  made  ade- 
quate, some  temporary  benefit  may  be  derived  from  the  use  of  a 


12 


Soil  Report  No. 


[March, 


soluble  salt  or  mixture  of  salts,  such  as  kainit,  which  contains  both 
potassium  and  magnesium  in  soluble  form  and  also  some  common 
salt  (sodium  chlorid).  About  600  pounds  per  acre  of  kainit  applied 
and  turned  under  with  the  raw  phosphate  will  help  to  dissolve  the 
phosphorus  as  well  as  to  furnish  available  potassium  and  mag- 
nesium, and  for  a few  years  such  use  of  kainit  will  no  doubt  be 
profitable  on  lands  deficient  in  organic  matter,  but  the  evidence  thus 
far  secured  indicates  that  its  use  is  not  absolutely  necessary  and  that 
it  will  not  be  profitable  after  adequate  provision  is  made  for  de- 
caying organic  matter,  since  this  will  necessitate  returning  to  the 
soil  either  all  produce  except  the  grain  (in  grain  farming)  or  the 
manure  produced  in  live-stock  farming.  (Where  hay  or  straw  are 
sold,  manure  should  be  bought.) 

Table  4. — Fertility  in  the  Soils  of  Clay  County,  Illinois 


Average  pounds  per  acre  in  4 million  of  subsurface  soil  (about  6-3  to  20  inches) 


Soil 

Total 

Total 

Total 

Total 

Total 

Total 

Lime- 

Lime- 

type 

Soil  type 

organic 

nitro- 

phos- 

potas- 

magne- 

cal- 

stone 

stone 

No. 

carbon 

gen 

phorus 

sium 

sium  , 

cium 

present 

required 

Upland  Prairie  Soils 


330 

Gray  silt  loam 

on  tight  clay 

28860 

3420 

1250 

53910 

13040 

7620 

6630 

328 

Brown-gray 

silt  loam  on 

tight  clay . . . 

18480 

2320 

1080 

54280 

11640 

5080 

6160 

329 

Drab  silt  loam 

35780 

2420 

1160 « 

50160 

8840 

11520 

3760 

326.1 

Brown  silt 

loam  on  clay 

54800 

5120 

1360 

48440 

11520 

13920 

4920 

331 

Deep  gray 

silt  loam  • 

34680 

3800 

1320 

49360 

7320 

7880 

5760 

Upland  Timber  Soils 


332 

Light-gray 

silt  loam  on 
tight  clay. . . 

9240 

1620 

1360 

57180 

13880 

6920 

13640 

332.1 

White  silt 

loam  on 
tight  clay. . . 

11600 

1120 

920 

60200 

10280 

8120 

8200 

334 

Yellow-gray 

silt  loam  . 

13760 

1520 

860 

64420 

14100 

7880 

1680 

335 

Yellow-silt 

loam 

15890 

1830 

790 

64480 

12720 

6840 

14270 

Ridge  Soils 


235 

Y ellow  silt 

loam 

48680 

5000 

1340 

61040 

23180 

9300 

12940 

233 

Gray-red  silt 

loam  on 

tight  clay. . . 

29000 

3480 

1240 

60680 

14880 

7760 

7880 

Swamp  and  Bottom-land  Soils 


1331 

Deep  gray 

silt  loam  ■ . 

25380 

2760 

2184 

70480 

15960 

12880 

1720 

1361 

Mixed  sandy 

loam 

31980 

3060 

1180 

63220 

10940 

13220 

200 

1315 

Drab  clay. . . . 

38480 

3800 

1360 

71320 

22440 

16040 

40 

1301 

Deep  peat*  . . . 

595320 

33580 

1860 

12380 

14480 

215800 

449360 

The  Subsurface  and  Subsoil 

In  Tables  4 and  5 are  recorded  the  amounts  of  plant  food  in  the  subsur- 
face and  subsoils,  but  it  should  be  remembered  that  these  supplies  are  of 
little  value  unless  the  top  soil  is  kept  rich.  Probably  the  most  important  in- 

*Amounts  reported  are  from  2 million  pounds  of  deep  peat. 


Clay  County 


13 


1911] 

formation  contained  in  Tables  4 and  5 is  that  all  of  the  upland  soils  are  even 
more  strongly  acid  in  the  subsurface  and  subsoil  than  in  the  surface,  thus 
emphasizing  the  importance  of  having  plenty  of  limestone  in  the  surface 
soil  to  neutralize  the  acid  moisture  which  rises  from  the  lower  strata  by 
capillary  action  during  periods  of  partial  drouth,  which  are  also  critical 
periods  in  the  life  of  such  plants  as  clover. 


Table  5.— Fertility  in  the  Soils  of  Clay  County,  Illinois 
Average  pounds  per  acre  in  6 million  pounds  of  subsoil  ( about  20  to  40  inches ) 


So  il 
type 
No. 

Soil  type 

Total 

organic 

carbon 

Total 

nitro- 

gen 

Total 

phos- 

phorus 

1 Total 
potas- 
sium 

Total 

mag- 

nesium 

Total 

cal- 

cium 

Dime- 

stone 

present 

Dime- 
stone  re- 
quired 

Upland  Prairie  Soils 

330 

Gray  silt  loam 

on  tight  clay 

20600 

2980 

2000 

88620 

33690 

19830 

20540 

328 

Brown-gray 

silt  loam  on 

tight  clay. . . 

12060 

2340 

2040 

87420 

33540 

18720 

4860 

329 

Drab  silt  loam 

34020 

2910 

1470 

77160 

19020 

17280 

16440 

326.1 

Brown  silt 

loam  on  clay 

53700 

5640 

1260 

69660 

24480 

26760 

13200 

331 

Deep  gray  silt 

loam 

24300 

3540 

1320 

78720 

17220 

11040 

17100 

Upland  Timber  Soils 


332 

Dight  gray  silt 

loam  on 

tight  clay. . . 

12680 

1910 

1830 

88110 

31420 

13680 

47060 

332.1 

White  silt 

loam  on 

tight  clay. . . 

11640 

1620 

1500 

91800 

15540 

10920 

25320 

334 

Y ellow-gray 

silt  loam .... 

13230 

1950 

1560 

96270 

29310 

10770 

20490 

335 

Y ellow  silt 

loam 

15200 

1720 

1160 

92480 

20760 

11880 

12280 

Ridge  Soils 


235 

Y ellow  silt 

loam 

26880 

3450 

1350 

95790 

31410 

20100 

10410 

233 

Gray-red  silt 

loam  on 

tight  clay. . . 

25020 

3360 

1800 

87720 

29280 

16620 

27360 

Swamp  and  Bottom-land  Soils 


1331 

Deep  gray 

silt  loam .... 

19260 

2470 

2940 

106300 

24240 

16620 

6590 

1361 

Mixed  sandy 

loam 

20130 

2100 

1350 

94350 

16890 

14760 

4350 

1315 

Drab  clay 

33600 

3660 

2040 

107040 

35880 

25680 

60 

1301 

Deep  peat*  . . . 

892980 

50370 

2790 

18570 

21720 

323700 

674040 

On  soils  which  are  subject  to  surface  washing,  including  especially  the 
yellow  silt  loam  of  the  upland  timber  area,  and  to  some  extent  the  yellow- 
gray  silt  loam,  and  the  ridge  soils  (and  even  the  gray  silt  loam  prairie  on 
rolling  areas),  the  supply  of  minerals  in  the  subsurface  and  subsoil  tend  to 
provide  for  a low-grade  system  of  permanent  agriculture  if  some  use  is 
made  of  legume  plants,  as  in  long  rotations  with  much  pasture,  because 
both  the  minerals  and  nitrogen  are  thus  provided  in  some  amount  almost 
permanently;  but  where  such  lands  are  farmed  under  such  a system  not 
more  than  two  or  three  grain  crops  should  be  grown  during  a period  of  io 
or  12  years,  the  land  being  kept  in  pasture  most  of  the  time;  and  a liberal 
use  of  limestone,  as  top  dressings  if  necessary,  and  occasional  reseeding 
with  clovers  will  benefit  both  the  pasture  and  indirectly  the  grain  crops. 

* Amounts  reported  are  from  3 million  pounds  of  deep  peat 


14 


Soil  Report  No.  i 


[March, 


Table  6. — Crop  Yields  per  Acre  on  DuBois  Experiment  Field 


On  Prairie  Land;  Gray  Silt  Loam  on  Tight  Clay 


Soil 

1902 

1903 

1904 

1905 

1906 

1907 

1908 

1909 

treatment 

Corn 

Oats 

Wheat 

Clover 

Corn 

Oats 

Wheat 

Soybeans 

applied 

bu. 

bu. 

bu. 

tons 

bu. 

bu. 

bu. 

bu. 

Land  not  Tile-drained 


None 

6 

9 

6 

1.3 

30 

19 

1 

3.5 

Lime 

7 

16 

7 

1.6 

35 

28 

8 

6.7 

Lime,  phosphorus. 
Lime,  phosphorus, 

13 

26 

25 

2.4 

39 

44 

18 

8.5 

and  potassium .. . 

12 

30 

28 

2.9 

49 

50 

21 

9.5 

Land  Tile-drained 


None 

1 

17 

3 

1.3 

33 

13 

4 

3.3 

Lime 

3 

17 

12 

1.7 

34 

24 

11 

6.2 

Lime,  phosphorus. 
Lime,  phosphorus, 

7 

28 

28 

2.3 

30 

32 

19 

7.2 

and  potassium.. . 

14 

26 

32 

3.0 

55 

44 

23 

10.3 

Average  of  Two  Series 


None  

Lime 

Lime,  phosphorus. 
Lime,  phosphorus, 
and  potassium. . . 

4 

5 
10 

13 

13 

17 

27 

28 

5 

9 

27 

30 

1.3 
1.7 

2.4 

2.9 

31 

34 

34 

52 

16 

26 

38 

47 

10 

19 

22 

3.4 

6.5 

7.9 

9.9 

Gain  for  lime  and 
phosphorus 

6 

14 

22 

1.1 

3 

22 

16 

4.5 

Value  of  increase.. 

$2.10 

$4.20 

$15.40 

$6.60 

$ 1.05 

$6.60 

$11.20 

$4.50 

Value  of  crops 
from  untreated 
land  

$1.40 

$3.40 

$ 3.50 

$7.80 

$10.85 

$4.80 

$ 2.10 

$3.40 

Results  of  Field  Experiments  at  Du  Bois 

Before  considering  in  detail  the  individual  soil  types,  it  seems  advisable 
to  study  some  of  the  results  already  obtained  where  definite  systems  of  soil 
improvement  have  been  given  an  actual  trial  in  different  parts  of  southern 
Illinois. 

In  Table  6 are  recorded  some  exceedingly  valuable,  trustworthy,  inter- 
esting and  instructive  data.  These  results  were  secured  by  eight  years  of 
actual  trial  on  the  most  common  type  of  soil  in  Clay  County,  which  is  also 
a very  common  type  in  Washington  County,  where  the  DuBois  Experiment 
Field  is  located. 

Anyone  of  common  sense  can  understand  this  table  if  he  is  willing  to 
study  jt. 

Has  tile-drainage  been  beneficial?  There  are  32  comparisons  which 
bear  upon  the  answer  to  this  question, — 8 with  no  soil  treatment,  8 with  lime 
applied,  8 with  lime  and  phosphorus,  and  8 comparisons  where  lime,  phos- 
phorus, and  potassium  were  used ; and  the  average  of  these  results  certainly 
does  not  justify  investing  in  tile  drainage  for  this  land. 

Does  the  application  of  lime  and  phosphorus  produce  benefit?  The  an- 
swer to  this  is  found  in  the  fact  that  the  value  of  the  eight  crops  on  the 
untreated  land  amounted  to  only  $3775,  whereas  the  value  of  the  increase 
produced  by  lime  and  phosphorus  was  $51.65.  In  other  words,  the  treat- 


Clay  County 


IS 


1911] 


ment  produced  more  than  the  land  did,  raising  the  crop  values  from  $37-75 
to  $89.40,  counting  corn  at  35  cents  a bushel,  oats  at  30  cents,  wheat  at 
70  cents,  hay  at  $6.00  a ton,  and  soybeans  at  $1.00  a bushel,  prices  which 
are  somewhat  below  the  10-year  average.  It  should  be  stated,  too,  that 
marked  improvement  was  made  in  quality  (especially  in  wheat  and  clover), 
which  is  not  given  credit  in  these  values. 

The  materials  used  per  acre  in  these  experiments  were  5 tons  of  burned 
lime  (applied  only  at  the  beginning),  1600  pounds  of  steamed  bone  meal 
(800  pounds  for  each  four-year  rotation),  and  800  pounds  of  potassium 
sulfate  (400  pounds  for  each  rotation)  ; but  other  investigations  (reported 
in  Circulars  no  and  127)  have  shown  that  ground  natural  limestone  and 
fine-ground  natural  rock  phosphate  are  more  economical  and  profitable  forms 
of  lime  and  phosphorus;  and  the  effect  produced  by  potassium  sulfate  can 
also  be  secured  at  much  less  expense  either  by  means  of  decaying  organic 
matter  (from  crop  residues,  green  manure  crops,  or  farm  manure)  or  by  the 
use  of  less  expensive  soluble  salts,  such  as  kainit,  as  shown  below.  If  we 
allow  $10  for  ground  limestone  (which  would  pay  for  the  full  equivalent 
of  the  lime  applied)  and  $20  for  the  bone  meal  (its  actual  cost),  we  find  that 
the  increase  produced  has  paid  for  these  materials  and  left  a net  profit  of 
$2.70  per  acre  per  annum,  or  70  percent  above  the  cost. 

Furthermore  about  one-half  of  the  lime  applied  and  at  least  two-thirds 
of  the  phosphorus  applied  still  remain  in  the  soil  for  the  benefit  of  future 
crops. 

The  potassium  applied  during  the  eight  years  cost  $20  and  produced 
increases  valued  at  $19.55,  leaving  a loss  of  6 cents  per  acre  per  annum, 
and  furthermore  the  potassium  removed  is  equal  to  the  total  amount  ap- 
plied. 

On  five  other  plots  in  the  Du.Bois  field  commercial  nitrogen  was  used 
alone  or  with  other  elements  during  the  first  three  years,  but  at  large  finan- 
cial loss,  and  with  no  apparent  residual  effect.  Since  1907,  a system  has 
been  adopted  for  those  plots  which  will  supply  both  the  nitrogen  and  or- 
ganic matter  by  means  of  legume  catch  crops  and  crop  residues,  but  an- 
other rotation  will  be  required  to  get  this  system  underway  so  as  to  pro- 
duce any  marked  effect  upon  crop  yields. 

Owing  to  the  severe  drouth  in  the  summer  of  1908,  the  clover  failed 
on  the  DuBois  field,  and  consequently  soybeans  were  substituted. 


Results  oe  Field  Experiments  at  Fairfield 

The  accompanying  photographic  reproductions  show  more  plainly  than 
words  or  figures  the  effect  and  the  importance  of  applying  limestone  and 
phosphorus  to  the  common  upland  soil  of  southern  Illinois.  These  photo- 
graphs were  taken  in  1910,  and  show  four  parts  of  a field  which  was  all 
seeded  alike  to  clover  in  1909.  This  40-acre  experiment  field  is  about  one 
mile  north  of  Fairfield,  in  Wayne  County,  which  adjoins  Clay  County  on 
the  south. 

The  Fairfield  Experiment  Field  is  divided  into  four  tracts  of  land,  and 
a four-year  rotation  is  practiced,  consisting  of  corn,  cowpeas  (or  soybeans), 
wheat,  and  clover.  If  the  clover  fails,  cowpeas  or  soybeans  may  be  substi- 
tuted for  that  season ; and  if  the  winter  wheat  fails,  oats  or  barley  may  be 
substituted  in  the  spring.  One  half  of  the  field,  or  20  acres,  is  tile-drained, 
while  the  other  half  has  only  the  ordinary  surface  drainage,  as  commonly 


16 


Soil  Report  No.  i 


[March, 


Plate  1.— Clover  on  Fairfield  Experiment  Field,  1910.  (The  first  crop,  shown 

IN  PHOTOGRAPHS,  WAS  CLIPPED  AND  LEFT  ON  THE  LAND;  THE  SECOND  CROP  PRODUCED 
NO  CLOVER  SEED  ON  THE  UNTREATED  LAND,  BUT  1|  BUSHELS  WERE  HARVESTED 
WHERE  THE  LIMESTONE  AND  PHOSPHATE  WERE  APPLIED) . 

provided  by  plowing  in  rather  narrow  lands  and  keeping  the  middle  fur- 
rows open. 

Grain  farming  is  practiced  on  half  of  the  tiled  land  and  also  on  half 
of  the  land  not  tiled ; while  live-stock  farming  is  practiced  on  the  other 
half  of  each  part.  A part  of  each  of  these  divisions  is  treated  with  2 tons 
of  limestone  and  i ton  of  fine-ground  raw  rock  phosphate,  per  acre,  every 
four  years,  while  another  part  is  not  so  treated. 

In  the  system  of  grain  farming  the  plan  is  to  return  to  the  land  all 
produce  except  the  grain  or  seed,  while  in  live-stock  farming  all  produce 
(or  its  equivilent)  is  to  be  used  for  feed  and  bedding  and  the  manure  re- 
turned to  the  land  in  proportion  to  the  crop  yields  produced  during  the 
previous  rotation.  It  should  be  stated,  however,  that  during  the  first  rota- 
tion the  manure  was  applied  in  the  same  amount  (8  tons  per  acre)  both 
where  limestone  and  phosphate  were  used  and  where  they  were  not  used ; but 
in  the  second  rotation,  as  when  manure  is  applied  to  the  19  io  clover  ground 
for  the  1911  corn  crop,  the  application  of  manure  will  be  in  direct  proportion 
to  the  crop  yields  produced  during  the  preceding  four  years.  Thus,  if  the 
land  treated  with  limestone  and  phosphate  has  produced  as  an  average,  one- 
half  larger  crops  of  corn,  cowpeas,  oats,  and  clover  during  1907,  1908, 
1909,  and  1910,  then  one-half  more  manure  will  be  applied  to  that  land 
for  the  1911  corn  crop,  than  to  the  land  which  receives  manure  alone.  Like- 
wise the  clover  and  other  crop  residues  returned  in  the  grain  system  during 
the  second  and  subsequent  rotations  will  be  in  proportion  to  the  yield  pro- 
duced on  the  respective  parts  of  the  field. 


Clay  County 


17 


1911] 


Plate  2.— Clover  on  Fairfield  Experiment  Field,  1910.  (The  first  crop,  shown  in 

PHOTOGRAPH,  MADE  1 TON  OF  FOUL  GRASS  WITH  BUT  LITTLE  CLOVER  WHERE  MANURE 
ALONE  WAS  USED,  AND  2§  TONS  OF  CLEAN  CLOVER  HAY  WHERE  THE  SAME  AMOUNT  OF 
MANURE  WAS  USED  WITH  LIMESTONE  AND  PHOSPHATE). 

The  best  plan  is  to  apply  the  phosphate  and  plow  it  under  with  manure 
or  other  organic  matter;  and  to  apply  the  limestone  immediately  after  the 
ground  is  plowed  for  wheat  in  order  that  it  may  be  mixed  with  the  sur- 
face soil  in  the  preparation  of  the  seed-bed  where  clover  is  to  be  seeded 
the  following  winter  or  spring.  However,  the  time  and  method  of  appli- 
cation are  very  secondary  matters;  the  important  thing  is  to  get  the  lime- 
stone and  phosphate  on  the  land  and  well  mixed  with  the  plowed  soil,  al- 
tho  it  is  better  to  mix  one  with  the  soil  before  applying  the  other,  because 
when  applied  in  intimate  contact  the  limestone  tends  temporarily  to  lessen 
the  availability  of  the  phosphorus,  probably  by  immediately  neutralizing  the 
nitric,  carbonic,  and  organic  acids  produced  in  the  decay  of  organic  matter. 

At  $1.25  a ton  for  limestone,  and  $7.50  a ton  for  rock  phosphate,  the 
cost  of  those  materials  amounts  to  $10  an  acre  every  four  years;  but  after 
three  or  four  rotations  the  phosphate  application  will  be  reduced  to  about 
one-half  ton,  which  will  reduce  the  annual  expense  to  about  $1.50  per  acre, 
an  expense  which  would  be  practically  covered  by  an  increase  of  4 bushels 
of  corn,  i]/2  bushels  of  cowpeas  or  soybeans,  2 bushels  of  wheat,  5 bushels 
of  oats,  or  J4  ton  of  hay. 

In  Table  7 are  recorded  the  crop  yields  obtained  since  the  work  was  be- 
gun on  the  land  on  which  the  1910  clover  fields  are  shown  in  the  photo- 
graphs. On  this  field  clover  was  sown  without  a nurse  crop  late  in  the 
season  of  1905,  and  the  1906  hay  crop  was  mostly  red  top,  the  land  hav- 
ing been  used  as  a red  top  meadow  previously. 


18 


Soil  Report  No.  i 


[March, 


Table  7 Crop  Yields  per  Acre  on  Fairfield  Experiment  Field 


On  Prairie  Land:  Gray  silt  Loam  on  Tight  Clay 


Soil 

1906 

1907 

1908 

1909 

1910 

treatment 

Clover  (?) 

Corn 

Cowpeas 

Oats 

Clover  (?) 

applied 

tons 

bu. 

bu. 

bu. 

crops 

Land  not  Tile-drained 


Limestone  and  phosphorus 

.50  45.4 

9.0 

35.7 

1.50  bu. 

None 

.20  34.2 

5.3 

29.9 

.00  bu. 

Manure 

.39  42.1 

7.4 

34.2 

1 .06  ton. 

Manure,  limestone,  phosphorus 

.48  52.4 

9.4 

40.9 

3.50  tons. 

Land  Tile-drained 


Limestone  and  phosphorus 

.12 

39.0 

7.7 

33.0 

.89  bu. 

None  

.10 

32.1 

4.7 

25.8 

.00  bu. 

Manure  

.25 

35.3 

5.4 

30.8 

.76  ton. 

Manure,  limestone,  phosphorus 

.44 

49.5 

11.5 

37.3 

3.62  tons. 

Average  of  both  Tiled  and  Untiled  Land 


Limestone  and  phosphorus 

None 

Manure 

.31 
.15 
.32 
. 46 

42.2 

33.2 
38.7 
51.0 

8.4 
5.0 

6.4 
10.5 

34.4 
27.9 

32.5 
39.1 

1.20  bu. 
.00  bu. 
.91  ton. 
3.56  tons. 

Manure,  limestone,  phosphorus 

Average  gain  for  limestone 

and  phosphorus 

.15 

10.6 

3.8 

6.5 

( 1.20  bu. 
(2.65  tons. 

Value  of  increase 

$ .90 

$3.71 

$3.80 

| $1.95 

j $ 7.20 
j $15.90 

Note Where  no  manure  is  applied  the  first  cutting  of  clover  is  left  on  the  land, 

the  second  cutting  saved  for  seed,  and  the  threshed  clover  straw  returned  to  the  land. 
The  photographs  show  the  1910  fields  in  both  the  grain  system  and  the  live-stock  sys- 
tem (first  crop). 


The  4-inch  tile  were  laid  in  the  fall  and  winter  of  1905-1906.  They 
were  placed  only  four  rods  apart,  half  of  the  strings  about  20  to  24  inches 
deep  and  the  other  half  about  36  to  40  inches  deep,  and  they  were  covered 
with  about  4 inches  of  cinders  before  the  ditches  were  filled.  They  have 
a satisfactory  grade  and  a good  outlet  is  provided.  The  tiled  land  is  some- 
what more  nearly  level  than  the  untiled  land,  altho  the  entire  field  is  what 
would  be  called  level  prairie  land. 

While  it  is  very  possible  that,  with  the  continued  use  of  clover  (the  “best 
subsoiler”)  in  the  rotation,  the  tile  drainage  may  ultimately  prove  to  be 
a profitable  investment,  it  is  plain  to  see  that  the  first  requisites  for  the 
improvement  of  this  soil  are  limestone,  phosphorus,  and  organic  matter. 

As  an  average  of  both  systems  of  farming  on  both  tiled  and  untiled  land,, 
the  increases  produced  by  limestone  and  phosphorus  during  the  first  rota- 
tion have  paid  $10.36*  an  acre,  or  more  than  they  cost  delivered  at  the 
average  railroad  station  in  southern  Illinois;  and  the  increase  in  the  two 

*Possibly  this  should  be  increased  or  decreased  slightly  because,  as  hereinafter  re- 
ported, on  one-half  of  the  land  under  experiment  potassium  salts  are  applied;  and,  while 
they  produce  practically  no  effect  on  the  manured  land,  the  effect  is  very  appreciable  on  the 
unmanured  land;  and  altho  the  potassium  salts  are  applied  to  one-half  of  the  check  plots 
the  same  as  to  one-half  of  the  land  receiving  limestone  and  phosphorus,  so  that  the  $10.36' 
is  the  actual  increase  produced  by  the  limestone  and  phosphorus  above  the  return  from  land 
otherwise  treated  the  same,  nevertheless  there  is  a possibility  that  on  part  of  the  land 
represented  in  this  summary  the  effect  of  the  potassium  salts  was  different  where  used  with 
limestone  and  phosphorus  than  where  used  alone.  No  potassium  salts  had  been  applied  to 
the  land  where  the  photographs  were  taken  or  to  the  land  from  which  the  reported  1910 
yields  of  clover  hay  or  seed  were  secured. 


101l\ 


Clay  County 


19 


cuttings  of  clover  hay  in  the  first  year  of  the  second  rotation  has  a value 
of  $15.90,  or  more  than  enough  to  pay  for  the  second  application  of  both 
limestone  and  phosphate,  thus  leaving  as  net  profit  any  increases  that  may 
be  produced  during  the  next  three  years;  and  these  increases  will  be  aug- 
mented because  of  the  larger  amount  of  organic  manures  to  be  returned  to 
the  better  yielding  land.  In  the  grain  system  the  limestone  and  phosphate 
produced  1.20  bushels  of  clover  seed,  valued  at  $7.20.  * 

Wheat  was  seeded  on  this  land  in  the  fall  of  1908,  but  it  was  winter- 
killed  so  completely  that  oats  were  seeded  in  the  spring  as  a substitute.  In 
1908,  wheat  on  another  series  of  plots  produced  4.1  bushels  on  untreated 
land,  13.7  bushels  where  limestone  and  phosphate  had  been  used,  6.0  bush- 
els where  manure  had  been  applied  for  corn  two  years  before,  and  18.6  bush- 
els per  acre  where  manure,  limestone,  and  rock  phosphate  had  been  ap- 
plied, thus  showing  an  average  increase  from  limestone  and  phosphorus  of 
11. 1 bushels.  In  1910,  on  still  other  series  of  plots  the  average  increase 
from  limestone  and  phosphorus  was  17  1 bushels  of  wheat,  19  bushels  of 
corn,  and  7.7  bushels  of  soybeans. 

Advantage  of  Crop  Rotation  and  Permanent  Systems 

It  should  be  noted  that  the  clover  is  not  likely  to  be  well  infected  with  the 
clover  bacteria  during  the  first  rotation ; but  even  a partial  stand  of  clover 
the  first  time  will  probably  provide  a thousand  times  as  many  bacteria  for 
the  next  clover  crop  as  one  could  afford  to  apply  in  artificial  inoculation, 
for  a single  root  tubercle  may  contain  a million  bacteria  developed  from  one 
during  the  season’s  growth. 

This  is  only  one  of  several  advantages  of  the  second  rotation  over 
the  first  four  years.  Thus  the  mere  practice  of  crop  rotation  is  an  advan- 
tage, especially  in  helping  to  rid  the  land  of  insects  and  foul  grass  and  weeds. 
The  deep-rooting  clover  crop  is  an  advantage  to  subsequent  crops  because 
of  that  characteristic.  The  larger  applications  of  organic  manures  are  a 
great  advantage;  and  in  systems  of  permanent  soil  improvement,  such  as 
are  here  advised  and  illustrated,  more  limestone  and  more  phosphorus  are 
provided  than  are  needed  for  the  meager  or  moderate  crops  produced  dur- 
ing the  first  rotation,  and  consequently  the  crops  in  the  second  rotation  have 
the  advantage  of  such  accumulated  residues  (well  incorporated  with  the 
plowed  soil)  in  addition  to  the  regular  applications  made  during  the  second 
rotation.  Thus,  with  the  crop  yields  shown  in  Table  7,  it  is  safe  to  say 
that  one-fourth  of  the  limestone  and  more  than  four-fifths  of  the  phos- 
phorus applied  remain  in  the  soil  at  the  end  of  the  first  four  years. 

This  means  that  these  systems  tend  positively  toward  the  making  of  rich 
land  from  poor  land — toward  the  making  of  $200  land  out  of  $50  land. 
The  ultimate  analyses  recorded  in  Tables  3,  4 and  5 give  the  absolute  in- 
voice of  these  southern  Illinois  soils.  They  show  that  they  are  positively 
deficient  only  in  limestone,  phosphorus,  and  nitrogenous  organic  matter; 
and  the  accumulated  information  from  careful  and  long-continued  investi- 
gations in  different  parts  of  the  United  States  positively  establish  the  fact 
that  in  general  farming  these  essentials  can  be  supplied  with  greatest  econ- 
omy and  profit  by  the  use  of  ground  natural  limestone,  very  finely  ground 
natural  rock  phosphate,  and  legume  crops  to  be  plowed  under  directly  or  in 
farm  manure.  No  other  applications  are  absolutely  necessary,  but,  as  already 
explained,  and  as  shown  in  Table  6,  the  addition  of  some  soluble  salt  in 
the  beginning  of  a system  of  improvement  on  these  soils  produces  some 


20 


Soil  Report  No.  i 


[March, 


temporary  benefit,  and  if  some  inexpensive  salt  such  as  kainit  is  used  it 
may  produce  sufficient  increase  to  more  than  pay  the  added  cost 

The  Potassium  Problem 

As  reported  in  Illinois  Bulletin  123,  where  wheat  has  been  grown  every 
year  for  more  than  half  a century  at  Rothamsted,  England,  exactly  the  same 
increase  was  produced  (5.6  bushels  per  acre),  as  an  average  of  the  first 
24  years,  whether  potassium,  magnesium,  or  sodium  was  applied,  the  rate 
being  200  pounds  of  potassium  sulfate  and  molecular  ecjuivalents  of  mag- 
nesium sulfate  and  sodium  sulfate.  As  an  average  of  58  years  (1852  to 
1909)  the  yield  of  wheat  has  been  12.8  bushels  on  untreated  land,  23.3 
bushels  where  86  pounds  of  nitrogen  and  29  pounds  of  phosphorus  per 
acre  per  annum  were  applied ; and,  as  further  additions,  85  pounds  of  potas- 
sium raised  the  yield  to  31.4  bushels;  52  pounds  of  magnesium  raised  it  to 

29.4  bushels;  and  50  pounds  of  sodium  raised  it  to  29.6  bushels.  Where 
potassium  was  applied  the  average  wheat  crap  removed  40  pounds  of  that 
element  in  the  grain  and  straw,  or  three  times  as  much  as  would  be  removed 
in  the  grain  only  for  such  crops  as  are  suggested  in  Table  1.  The  Rotham- 
sted soil  contained  abundance  of  limestone,  but  no  organic  matter  was  pro- 
vided except  the  little  in  the  stubble  and  roots  of  the  wheat  plants. 

On  another  field  at  Rothamsted  the  average  yield  of  barley  for  58  years 
(1852  to  1909)  has  been  14.5  bushels  on  untreated  land,  38.8  bushels  where 
43  pounds  of  nitrogen  and  29  pounds  of  phosphorus  have  been  applied  per 
acre  per  annum;  while  the  further  addition  of  85  pounds  of  potassium,  19 
pounds  of  magnesium,  and  14  pounds  of  sodium  (all  in  sulfates)  raised  the 
average  yield  to  41.7  bushels,  but,  where  only  70  pounds  of  sodium  were 
applied  in  addition  to  the  nitrogen  and  phosphorus,  the  average  has  been 

43.4  bushels.  Thus,  as  an  average  of  58  years,  the  use  of  sodium  produced 
1.8  bushels  less  wheat  and  1.7  bushels  more  barley  than  the  use  of  potas- 
sium. with  both  grain  and  straw  removed  and  no  organic  manures  returned. 

While  about  half  of  the  potassium,  nitrogen,  and  organic  matter,  and 
about  one-fourth  of  the  phosphorus,  contained  in  manure,  will  be  lost  by 
three  or  four  months’  exposure  in  the  ordinary  pile  in  the  barn  yard,  there 
is  practically  no  loss  if  plenty  of  absorbent  bedding  is  used  on  cement  floors, 
and  if  the  manure  is  hauled  to  the  field  and  spread  within  a day  or  two 
after  it  is  produced.  Again,  while  the  animals  destroy  two-thirds  of  the 
organic  matter  and  retain  one-fourth  of  the  nitrogen  and  phosphorus  in 
average  live-stock  farming,  they  retain  less  than  one-tenth  of  the  potassium, 
from  the  food  consumed ; so  that  the  actual  loss  of  potassium  in  the  pro- 
ducts sold  from  the  farm,  either  in  grain  farming  or  in  live-stock  farming, 
is  wholly  negligible  on  land  containing  25,000  pounds  or  more  of  potas- 
sium in  the  surface  6^3  inches. 

The  removal  of  one  inch  of  soil  per  century  by  surface  washing  (which 
is  likely  to  occur  wherever  there  is  satisfactory  surface  drainage)  would 
permanently  maintain  the  potassium  in  grain  farming  by  renewal  from  the 
subsoil,  provided  one-third  of  the  potassium  is  removed  by  cropping  be- 
fore the  soil  is  carried  away.  Thus,  aside  from  the  peat  soil,  there  is  no 
soil  in  Clay  County  which  contains  less  than  3,600  pounds  of  potassium  per 
acre-inch.  One-third  of  this  is  1200  pounds,  while  100  years  of  grain  farm- 
ing would  carry  away  from  the  farm  only  1275  pounds  of  potassium  in  the 
grain  and  seed  of  such  crops  as  are  mentioned  in  Table  1. 


Clay  County 


21 


1911] 


From  all  of  these  facts  it  will  be  seen  that  the  potassium  problem  is  not  one 
of  supply  but  of  liberation ; and  the  Rothamsted  records  show  that  other  sol- 
uble salts  have  practically  the  same  power  as  potassium  to  increase  crop  yields 
in  the  absence  of  sufficient  decaying  organic  matter.  Whether  this  action 
relates  to  supplying  or  liberating  potassium  for  its  own  sake,  or  to  the 
power  of  the  soluble  salt  to  increase  the  availability  of  phosphorus  or  other 
elements,  is  not  known,  but  where  much  potassium  is  removed,  as  in  the 
entire  crops  at  Rothamsted  with  no  return  of  organic  residues,  probably  the 
soluble  salt  functions  in  both  ways. 

As  an  average  of  84  separate  tests  conducted  in  1907,  1908,  and  1909, 
on  the  Fairfield  Experiment  Field,  an  application  of  200  pounds  of  potas- 
sium sulfate,  containing  85  pounds  of  potassium  costing  $5.10,  increased  the 
yield  of  corn  by  7.9  bushels  per  acre;  while  600  pounds  of  kainit,  contain- 
ing only  60  pounds  of  potassium  and  costing  $4.00,  gave  an  increase  of 
10.6  bushels.  Thus,  at  40  cents  a bushel  for  corn,  the  kainit  has  paid  for 
itself;  but  these  results,  like  those  at  Rothamsted  and  DuBois,  were  se- 
cured where  no  adequate  provision  had  been  made  for  decaying  organic 
matter. 

Additional  experiments  at  Fairfield  include  an  equally  complete  test  with 
potassium  sulfate  and  kainit  on  land  to  which  8 tons  per  acre  of  farm  ma- 
nure had  been  applied.  As  an  average  of  84  tests  with  each  material,  the 
200  pounds  of  potassium  sulfate  increased  the  yield  of  corn  by  .8  bushel 
while  the  600  pounds  of  kainrt  gave  an  increase  of  1.1  bushels.  Thus, 
where  organic  manure  was  supplied,  practically  no  effect  was  produced  by 
the  addition  of  either  potassium  sulfate  or  kainit;  in  part  perhaps  because 
the  potassium  removed  in  the  crops  is  mostly  returned  in  the  manure  if 
properly  cared  for;  and  perhaps  in  larger  part  because  the  decaying  or- 
ganic matter  helps  to  liberate  and  held  in  solution  other  plant  food  elements, 
especially  phosphorus. 

In  laboratory  experiments  at  the  Illinois  Experiment  Station,  it  has 
been  shown  that  potassium  salts  and  most  other  soluble  salts  increase  the 
solubility  of  the  phosphorus  in  soil  and  in  rock  phosphate  as  determined  by 
chemical  analysis;  also  that  the  addition  of  glucose  with  rock  phosphate  in 
pot-culture  experiments  increases  the  availability  of  the  phosphorus,  as  meas- 
ured by  plant  growth,  altho  the  glucose  consists  only  of  carbon,  hydrogen, 
and  oxygen,  and  thus  contains  no  plant  food  of  value. 

If  we  remember  that,  as  an  average,  live  stock  destroy  two-thirds  of 
the  organic  matter  of  the  food  consumed,  it  is  easy  to  determine  from 
Table  1 that  more  organic  matter  will  be  supplied  in  a proper  grain  sys- 
tem than  in  a strictly  live-stock  system ; and  the  evidence  thus  far  secured 
from  older  experiments  at  the  University  and  at  other  places  in  the  state 
indicates  that  if  the  corn  stalks,  straw,  clover,  etc.  are  incorporated  with 
the  soil  as  soon  as  practicable  after  they  are  produced  (which  can  usually 
be  done  in  the  late  fall  or  early  spring),  there  is  little  or  no  difficulty  in 
securing  sufficient  decomposition  in  our  humid  climate  to  avoid  serious  in- 
terference with  the  capillary  movement  of  the  soil  moisture,  a common 
danger  from  plowing  under  too  much  coarse  manure  of  any  kind  in  the 
late  spring  of  a dry  year. 

If,  however,  the  entire  produce  of  the  land  is  sold  from  the  farm,  as 
in  hay  farming,,  or  when  both  grain  and  straw  are  sold,  of  course  the  draft 
on  potassium  will  then  be  so  great  that  in  time  it  must  be  renewed  by  some 
sort  of  application.  As  a rule,  such  farmers  ought  to  secure  manure  from 
town,  since  they  furnish  the  bulk  of  the  material  out  of  which  the  manure 
is  produced. 


22 


Soil  Report  No. 


[March, 


INDIVIDUAL  SOIL  TYPES 
(a)  Upland  Prairies 
Gray  Silt  Loam  on  Tight  Clay  ( jjo ) 

This  is  the  predominating  type  of  soil  in  the  lower  Illinoisan  glaciation  and 
greatly  exceeds  any  other  type  in  Clay  County,  the  area  being  100,720  acres, 
or  37  percent  of  the  area  of  the  county.  Its  topography  is  nearly  level  or 
gently  undulating,  tho  in  places  somewhat  rolling. 

The  type  variations*  are  due  primarily  to  three  things : ( 1 ) the  organic 

matter  content;  (2)  the  topography  and  consequent  surface  drainage;  and 
(3)  the  depth,  thickness,  and  density  of  the  tight  clay  layer.  Adjoining 
the  somewhat  rolling  areas  or  in  the  vicinity  of  ridges,  this  type  has  received 
some  wash  that  has  buried  the  tight  clay  to  such  depths  that  it  is  less  ob- 
jectionable, and  generally  made  it  a better  soil  than  the  average.  This  is 
particularly  noticeable  in  parts  of  Townships  3 and  4,  Range  5. 

In  some  of  the  low  areas  that  grade  toward  drab  silt  loam  (329),  or 
brown  silt  loam  -on  clay  (326.1)  the  organic  matter  content  is  higher  in 
the  subsurface  and  subsoil,  giving  a better  phase  of  the  type.  This  fact  is 
noticeable  in  certain  areas  in  Townships  4 and  5,  Range  7,  and  to  a less  ex- 
tent in  small  areas  in  Township  3,  Range  6. 

The  surface  stratum,  o to  6^  inches,  consists  of  a friable,  silt  loam, 
varying  from  light  to  dark  gray  in  color  and  containing  sufficient  clay  to 
make  it  slightly  plastic  when  wet.  A few  small  gravels  of  quartz  and  concre- 
tions of  hydrated  iron  oxid  are  sometimes  found  in  it.  The  organic  matter 
content  varies  somewhat  from  an  average  of  2.4  percent  as  determined  from 
the  total  organic  carbon.  The  surface  soil  is  fairly  pervious  to  water  but 
the  low  organic  matter  content  and  lack  of  granulation  render  it  in  poor 
tilth,  causing  it  to  “run  together”  very  readily  from  heavy  rains  or  by  freez- 
ing and  thawing  when  wet. 

The  subsurface  soil,  averaging  about  13  inches  in  thickness,  varies  from 
a gray  silt  loam  to  a very  light  gray  or  even  white  silt.  The  upper  part  of 
this  stratum  is  sometimes  about  the  same  in  color  as  the  surface  soil,  but 
much  oftener  the  plowline  marks  the  beginning  of  a much  lighter  colored 
soil,  which  becomes  still  lighter  with  depth,  passing  into  a distinct  “gray 
layer,”  varying  in  thickness  from  2 to  10  inches.  This  “gray  layer”  is 
deficient  in  organic  matter,  close-grained,  very  compact  when  dry,  and  quite 
slowly  pervious  to  water.  When  saturated,  it  is  soft,  and  posts  may  be  driven 
very  readily  thru  it.  A few  small  quartz  gravels  and  some  concretions  of 
hydrated  iron  oxid  may  be  present  in  this  stratum. 

The  subsoil  averages  about  20  inches  from  the  surface  but  varies  from 
only  a few  inches  on  the  “scalds”  to  2 feet  or  more  on  the  best  phase  of  the 
type.  It  is  usually  made  up  of  two  distinct  layers,  the  upper  tight  clay,  or 
so-called  “hardpan,”  and  a lower,  friable,  porous,  silty  layer.  «The  former 

*This  type  also  contains  many  small  unproductive  areas  known  as  “scalds”  or  “scald 
spots”  readily  recognized  in  a plowed  field  by  their  light  color.  Occasionally  one  of  these 
spots  may  cover  several  acres  but  ordinarily  these  areas  are  only  a few  square  rods.  On 
these  spots  the  ordinary  surface  soil,  and,  in  many  cases,  the  subsurface  soil,  is  almost 
absent,  thus  bringing  the  subsoil  to  or  very  near  the  surface  which  constitutes  the  “scald" 
These  spots  are  very  irregular  in  their  occurrence,  some  fields  being  entirely  free  from 
them,  while  in  others  there  may  be  several  or  many.  Bracted  plantain  (sometimes  less 
properly  called  buckhorn)  of  stunted  growth  is  a common  plant  upon  these  “scalds”. 


I9ii] 


Clay  County 


23 


varies  from  2 or  3 to  more  than  12  inches  in  thickness  and  is  usually  a 
tight,  silty  clay,  reddish  or  yellowish  in  color,  very  sticky  and  gummy  when 
wet  and  very  hard  when  dry. 

As  a rule,  the  drainage  of  this  type  is  rather  poor,  due  to  one  or  both 
of  two  causes,  (1)  the  lay  of  the  land,  and  (2)  the  tight  clay  subsoil.  It 
is  still  a question  whether  it  can  be  tile-drained  profitably;  but  experiments 
now  in  progress  will  ultimately  answer  the  question.  Usually  the  surplus 
water  can  be  disposed  of  fairly  well  by  giving  proper  attention  to  surface 
drainage,  by  means  of  ditches  and  furrows. 

For  the  economical  and  permanent  improvement  of  this  soil,  adopt  a 
good  rotation  of  crops,  including  about  one-third  legume  crops,  plow  under 
everything  except  the  grain  and  seed  (in  grain  farming)  or  make  and  use 
as  much  manure  as  possible  (in  live-stock  farming),  and  apply  about  1000 
pounds  of  limestone  and  200  pounds  of  raw  phosphate,  per  acre,  for  each 
year  in  the  rotation,  as  explained  above.  (Heavier  initial  application  should 
be  made  if  possible.) 

Brozvn-Gray  Silt  Loam  on  Tight  Clay  {328) 

This  type  occupies  only  small  areas,  totaling  960  acres  in  this  county,  but 
forms  the  prevailing  type  in  the  transitional  area  between  the  middle  and 
lower  Illinoisan  glaciation.  However,  small  isolated  areas  are  found  in  the 
heart  of  the  lower  Illinoisan  glaciation.  With  few  exceptions  the  topography 
is  flat  or  only  slightly  undulating. 

This  type  contains  “scalds,”  where  the  subsoil  comes  to  the  surface  or 
injuriously  near  it.  These  are  very  irregular  in  their  occurrence,  some  fields 
being  devoid  of  them,  while  in  others  they  are  numerous. 

The  surface  soil,  o to  62/s  inches,  is  a dark  gray  to  brown  silt  loam, 
varying  in  color  with  its  gradation  toward  other  types.  It  contains  about  2.8 
percent  of  organic  matter  and  has  a small  amount  of  clay  and  some  fine 
sand,  but  medium  and  coarse  silt  predominates.  It  is  porous,  friable  and 
easy  to  work. 

The  subsurface  stratum  varies  much  as  to  thickness  and  color.  The 
average  thickness  is  10  to  12  inches  altho  it  may  be  entirely  absent  in 
some  places  and  in  others  18  inches  or  more  in  thickness.  It  consists  of  a 
grayish  brown  silt  loam,  the  color  becoming  lighter  with  depth.  There  is 
usually  a distinct  gray  or  grayish  brown  layer  just  above  the  subsoil,  which 
varies  in  thickness  from  2 to  10  inches.  Where  the  type  grades  into  the 
gray  silt  loam  on  tight  clay  (330)  this  layer  may  become  quite  well  de- 
veloped and  partake  somewhat  of  the  impervious  character  of  the  corres- 
ponding layer  in  that  type. 

The  subsoil  is  found  at  variable  depths  from  only  a very  few  inches  on 
the  “scalds”  to  2 feet  or  more  on  the  better  phase  of  this  type.  It  con- 
sists of  two  distinct  layers,  the  upper,  a plastic,  gummy,  yellow,  drab,  or 
dark  olive-colored  clay,  very  tight  and  nearly  impervious  to  water.  This 
stratum  is  from  3 to  18  inches  thick  and  below  it  is  a clayey  silt,  friable 
and  pervious,  of  a yellow  color  or  yellow  with  drab  mottlings. 

The  upper  layer  of  the  subsoil  is  too  impervious  to  allow  good  under- 
drainage, so  that  special  surface  drainage  is  commonly  provided.  The 
discussion  of  tile  drainage  for  the  gray  silt  loam  on  tight  day  (330)  applies 
as  well  to  this  tvpe. 

In  general  the  same  system  of  improvement  should  be  adopted  as  for 


24 


Soil  Report  No.  i 


[March, 


the  gray  silt  loam  on  tight  clay,  altho  the  brown-gray  silt  loam  contains 
somewhat  more  nitrogen  and  phosphorus  in  the  surface  soil  and  less  acidity 
in  the  subsoil.  However,  the  difference  in  the  plowed  soil  of  an  acre 
amounts  to  only  about  20  loads  of  manure  and  1 ton  of  phosphate,  and  the 
nitrogen  is  in  the  less  active  form  of  old  humus. 

Drab  Silt  Loam  (329) 

Some  of  the  low  and  more  poorly  surface-drained  areas  of  the  prairie 
land  have  received  deposits  of  finer  material  \yashed  in  from  the  slightly 
higher  surrounding  land,  and  a greater  accumulation  of  organic  matter 
has  taken  place,  more  particularly  in  the  subsurface  and  subsoil,  owing  to 
the  more  luxuriant  growth  of  vegetation  and  the  better  conditions  for  pre- 
venting complete  decay.  This  has  given  rise  to  a type  of  soil,  the  drab 
silt  loam  (329)  which  is  darker  in  color,  better  in  texture,  and  somewhat 
more  productive  than  the  surrounding  gray  silt  loam  on  tight  clay  (330), 
the  ordinary  prairie  of  this  glaciation.  The  drab  silt  loam  (329)  needs  un- 
der-drainage to  bring  it  to  its  best  condition  of  tilth  and  productiveness; 
and  the  physical  composition,  texture,  and  structure  indicate  that  tile  drain- 
age will  greatly  benefit  this  soil,  but  actual  field  experiments  are  necessary 
to  determine  how  satisfactorily  tile  will  work.  With  the  limited  appropria- 
tion hitherto  provided  for  the  investigation  of  Illinois  soils,  it  has  not  been 
possible  for  the  University  to  establish  an  experiment  field  upon  this  soil 
type  which  is  of  very  considerable  importance,  not  only  because  of  the  14,- 
400  acres  of  this  type  in  Clay  County,  but  also  because  of  its  presence  in 
most  other  counties  in  the  lower  Illinoisan  glaciation. 

The  surface  stratum  of  the  drab  silt  loam  (329)  is  a dark  drab  to 
brown  silt  loam,  the  former  color  predominating.  The  physical  composi- 
tion and  texture  of  this  soil  indicate  that  it  will  work  up  well  when  thoroly 
drained. 

The  subsurface  varies  from  a dark  gray  to  a drab  silt  loam,  frequently 
with  blotches  of  yellow  iron  oxid.  The  amount  of  clay  varies  consider- 
ably, the  stratum  being  very  silty  in  some  areas  while  in  others  it  has  suf- 
ficient clay  to  make  it  plastic,  but  in  either  case  i^  pervious  to  water. 

The  subsoil  varies  in  color  from  drab  to  yellowish  gray  with  sometimes 
irregular  blotches  of  all  mixed  together,  while  in  physical  composition  it 
varies  from  a friable  silt  to  a clay.  The  subsoil  is  rather  heavy  yet  it  is 
sufficiently  pervious  so  that  tile  drains  will  very  probably  work  well,  and 
there  are  very  few  areas  of  this  type  that  would  not  be  greatly  benefited  by 
efficient  under-drainage. 

The  variations  of  this  type  are  due  to  gradations  toward  other  types. 
Where  it  is  grading  toward  the  gray  silt  loam  on  tight  clay  (330)  or  the 
light  gray  silt  loam  on  tight  clay  (332),  the  soil  becomes  lighter  in  color 
and  the  subsurface  more  silty,  while  the  subsoil  becomes  lighter  and  less 
pervious  to  water.  If  the  type  is  grading  toward  brown  silt  loam  it  be- 
comes darker  and  slightly  heavier.  When  drained  and  properly  treated  it 
promises  to  become  one  of  the  best  types  in  southern  Illinois,*  because  of 
the  absence  of  the  gray  layer  and  tight  clay  stratum  in  the  subsurface  and 
subsoil. 

From  the  standpoint  of  fertility  and  methods  of  improvement  the  drab 
silt  loam  does  not  differ  essentially  from  the  more  common  gray  silt  loam 
prairie  land;  but  with  equal  provisions  for  drainage  and  plant  food  the 


Clay  County 


25 


1911] 


drab  silt  loam  will  be  a more  productive  soil,  especially  in  very  wet  or  very 
dry  seasons,  because  of  its  more  pervious  character  and  consequent  greater 
power  to  handle  moisture,  not  only  by  permitting  the  downward  flow  when 
saturated  and  the  upward  capillary  rise  from  the  lower  subsoil  in  time  of 
drouth,  but  also  because  of  its  greater  capacity  for  absorbing  and  retaining 
moisture;  and  of  course  it  also  furnishes  a greater  feeding  range  for  plant 
roots  than  the  less  porous  types. 


Brown  Silt  Loam  on  Clay  (326.1) 

The  areas  of  this  type  occur  in  about  the  same  location  as  those  of  the 
drab  silt  loam  (329),  but  have  received  more  wash  from  adjoining  higher 
land.  It  contains  more  organic  matter  in  the  subsurface  and  subsoil  than 
any  other  upland  type  in  the  county.  It  is  a good  soil  physically  but,  like 
the  drab  silt  loam,  needs  under-drainage.  The  total  area  in  the  county  is 
only  824  acres. 

The  surface  soil  is  a dark  brown  to  black  silt  (or  clayey  silt)  loam, 
rather  plastic  when  wet,  but  somewhat  granular  under  proper  conditions  for 
granulation. 

The  subsurface  stratum  differs  from  the  surface  in  having  a slightly 
lighter  color  and  containing  more  clay,  there  being  sufficient  to  render  it  quite 
plastic. 

The  subsoil  is  a brownish  or  dark  drab  silty  clay  somewhat  impervious 
but  probably  susceptible  of  satisfactory  drainage.  While  tile  will  probably 
not  draw  as  far  in  this  type  or  in  the  drab  silt  loam  (329)  as  in  some  corn 
belt  types,  yet  by  putting  the  lines  of  tile  from  four  to  eight  rods  apart  this 
land  could  all  be  well  drained,  so  far  as  can  be  judged  from  physical  char- 
acteristics. 

The  nitrogen  content  of  the  subsurface  and  subsoil  is  naturally  higher 
because  it  is  one  of  the  constituents  of  the  organic  matter,  but  such  organic 
nitrogen,  particularly  in  those  strata,  becomes  available  too  slowly  to  be  a 
factor  of  great  significance;  and,  like  the  other  types  already  described,  the 
essential  requirements  for  the  improvement  of  this  soil  are  limestone,  phos- 
phorus, and  nitrogenous  organic  matter. 

Deep  Gray  Silt  Loam  ( 331 ) 

This  type  occurs  in  low,  poorly  drained  areas  that  have  received  a con- 
siderable amount  of  material  washed  from  the  surrounding  higher  lands,  but 
the  material  deposited  contains  less  clay  than  that  received  by  the  previously 
described  types  of  similar  topography. 

The  surface  soil  is  a gray  to  dark  gray  silt  loam,  under  which  to  a depth 
of  40  inches  is  a gray  silt  loam  or  gray  silt  that  differs  from  the  surface 
chiefly  in  having  a lighter  color.  Locally  a stratum  of  clayey  silt  may  be 
developed  at  about  36  inches  in  depth.  This  soil  will  certainly  underdrain, 
and  when  drained  will  become  very  productive  with  proper  treatment. 

As  will  be  seen  from  Tables  3,  4,  and  5,  this  type  averages  about  as  high 
in  acidity  and  rather  lower  in  plant  food  than  any  of  the  other  prairie  types. 
The  greater  porosity  and  deeper  feeding  range  for  plants  are  distinct  advan- 
tages; but  the  same  systems  of  improvement  should  be  followed. 


26 


Soil  Report  No. 


[March, 


(b)  Timber  Uplands 
Light  Gray  Silt  Loam  on  Tight  Clay  ( S32 ) 

This  type  occurs  in  old  timbered  regions  where  the  land  ia  so  nearly  level 
that  there  is  no  chance  for  rapid  surface  drainage.  The  type  was  originally 
the  same  as  the  gray,  silt  loam  on  tight  clay  (330)  but  has  a lower  organic 
matter  content  because  of  the  long-continued  growth  of  timber.  The  upland 
soils  that  were  timbered  for  centuries  have  less  organic  matter  and  are  con- 
sequently much  lighter  in  color  than  the  adjoining  prairie  because  of  the 
fact  that  forest  trees  add  very  little  organic  matter  to  the  soil  whereas  the 
process  of  decomposition  is  going  on  more  or  less  rapidly  in  all  soils.  The 
leaves  and  twigs  of  the  trees  fall  upon  the  surface  of  the  ground  and  decay 
completely;  whereas  the  prairie  grasses  form  a mass  of  roots  in  the  soil 
which,  when  they  die,  are  prevented  from  complete  decay  by  the  absence  of 
sufficient  oxygen.  In  this  way  prairie  grasses  and  other  plants  cause  a grad- 
ual accumulation  of  organic  matter.  If  prairie  land  becomes  forested  the 
organic  matter  is  slowly  diminished  to  a low  point.  The  average  amount  of 
organic  matter  in  the  upland  timber  soils  of  the  state  is  2 percent  while  the 
prairie  soils  have  5.3  percent,  the  corn  belt  -soils  being  included  in  both  cases. 
Some  of  the  level  timber  soils  are  so  depleted  in  this  constituent;  that  they  do 
not  have  over  1 percent  in  the  surface  stratum. 

This  type  has  two  distinct  phases,  one  a slightly  better  surface-drained 
but  lighter  colored,  and  less  productive,  and  the  other  the  more  swampy  areas 
(where  water  oaks  commonly  grew),  a darker  surface  and  more  porous  soil, 
so  that  better  dramage  is  probably  possible.  The  amount  of  this  latter 
phase  is  small  as  compared  with  the  former  and  is  frequently  confined  to 
narrow  strips  too  small  to  map. 

“Scalds”  are  found  upon  this  type  but  are  not  so  common  as  upon  the 
gray  silt  loam  on  tight  clay  (330)  or  brown  gray  silt  loam  on  tight 
clay  (328). 

The  surface  soil  of  the  most  common  level  timber  land  (332)  of  this 
glaciation  is  a light  gray  to  almost  white  silt  loam  containing  about  1 y2  per- 
cent of  organic  matter.  It  is  somewhat  porous  and  incoherent  but  contains 
sufficient  clay  to  bake  when  puddled  and  dried.  When  the  moisture  content 
is  at  its  optimum  it  works  very  well,  but  because  of  the  low  organic  matter 
content  it  is  “run  together”  badly  by  rains  or  by  freezing  and  thawing  when 
wet.  This  layer  as  well  as  the  subsurface  and  subsoil  contains  large  numbers 
of  iron  oxid  concretions  of  various  sizes  up  to  one-fourth  inch  in  diameter. 
Small  pebbles  of  quartz  are  sometimes  found,  possibly  having  been  brought 
to  the  surface  from  the  underlying  glacial  till  by  burrowing  animals  during 
past  centuries. 

The  subsurface  varies  from  a light  gray  silt  loam  to  a white  silt,  compact 
but  friable,  from  2 to  20  inches  in  thickness.  Water  passes  thru  it  slowly. 

The  subsoil  consists  of  a compact  yellowish  gray  clayey  silt  or  silty  clay, 
only  slowly  pervious  to  water,  but  usually  not  quite  so  tight  as  the  correspond- 
ing layer  of  the  gray  silt  loam  on  tight  clay  (330).  In  places  the  type  has 
a somewhat  more  friable  subsoil  and  is  not  so  impervious  as  the  above,  and 
where  the  tight  clay  occurs  at  the  greater  depths  from  the  surface  it  is  less 
objectionable. 

The  invoice  of  plant  food  shews  great  need,  of  nitrogen  and  phosphorus, 
and,  with  these  and  a liberal  use  of  limestone  and  organic  matter,  the  soil 
can  be  made  highly  productive  with  proper  surface  drainage. 


Clay  County 


27 


J911] 


White  Silt  Loam  on  Tight  Clay  (3s2-1) 

This  type  is  found  on  the  level  upland  and  is  or  has  been  covered  by  a 
growth  of  stunted  trees  principally  the  so-called  post  oak.  The  term  post- 
oak flat  or  post-oak  soil  is  commonly  applied  to  this  type  altho  these  terms 
are  often  applied  locally  to  the  poorer  phase  of  light  gray  silt  loam  on  tight 
clay  (332).  The  surface  drainage  is  very  poor  and  the  subsoil  is  almost  im- 
pervious. The  total  mapped  area  in  the  county,  is  only  224  acres,  but  there 
are  many  small  areas  of  this  type  that  cannot  be  shown  on  the  map,  and 
much  of  the  light-gray  Silt  loam  on  tight  clay  (332)  grades  toward  this 
related  type  (332.1). 

Where  the  type  has  been  cultivated,  the  surface  soil  is  a white  silt,  while 
in  the  timbered  areas  there  may  be  an  inch  or  two  of  dark  gray  silt  loam 
underlain  by  the  characteristic  white  silt.  The  organic  matter  content  is  even 
lower  than  in  the  preceding  type.  Because  of  this  and  the  high  silt  content, 
the  soil  “runs  together”  badly.  Iron  oxid  concretions  are  always  present. 

The  subsurface  layer  is  a white  silt  with  many  iron  oxid  concretions. 
The  thickness  varies  from  4 to  16  inches,  passing  abruptly  into  the  subsoil 
which  is  a light  yellow,  iron-stained  silty  clay,  very  tough  and  plastic  when 
wet  and  hard  when  dry.  Both  subsurface  and  subsoil  are  almost  impervious 
and  when  these  layers  are  dry  water  moves  down  into  them  with  extreme 
slowness. 

In  nitrogen  and  phosphorus  this  is  one  of  the  poorest  soils  found  in  the 
state,  the  total  in  the  surface  soil  6%  inches  deep  being  about  equal  to  the 
needs  of  three  rotations  in  nitrogen  and  of  five  rotations  in  phosphorus,  with 
such  crops  as  are  suggested  in  Table  1 ; and  with  no  provision  to  make  plant 
food  available  the  crops  produced  on  this  type  are  often  not  worth  raising. 
With  liberal  use  of  limestone,  phosphorus,  and  organic  matter  this  soil  can 
be  markedly  and  profitably  improved  where  the  surface  drainage  is  adequate ; 
but,  like  all  soils  with  tight  clay  subsoils,  it  will  not  be  a good  soil  for  very 
wet  or  very  dry  seasons. 

Yellow-Gray  Silt  Loam  (334) 

This  type  lies  between  the  yellow  silt  loam  (335),  on  the  one  hand,  and 
the  gray  silt  loam  on  tight  clay  (330)  or  light  gray  silt  loam  on  tight  clay 
(332)>  on  the  other,  and  it  is  somewhat  intermediate,  in  character.  For  gen- 
eral agricultural  purposes  it  is  one  of  the  best  types  of  soil  in  the  county, 
provided  it  exists  in  large  areas;  whereas  small  areas  are  sometimes  almost 
valueless  because  of  scald  spots. 

The  common  topography  is  undulating  but  varies  from  nearly  level  to 
almost  broken  land.  The  slopes  are  rather  long  and  gentle,  but  in  places  very 
short  abrupt  slopes  of  yellow  silt  loam  occur  which  are  too  small  in  area  to 
show  separately  on  the . map.  The  surface  drainage  is  generally  good,  in 
fact  so  good  that  there  is  considerable  washing  going  on  where  the  methods 
of  culture  are  not  the  best  for  preventing  it.  While  this  type  was  generally 
timbered,  it  sometimes  extends  out  into  the  prairie  along  natural  drainage 
channels  and  as  these  particular  areas  represent  recent  erosion  of  the  prairie, 
it  shows  “scalds”  or  tight  clay  outcrops,  the  presence  of  which  renders  these 
narrow  areas  very  inferior  to  the  type  generally,  and  in  some  places  almost 
worthless.  These  numerous  “scald”  areas  are  rarely  over  two  or  three  acres 


28 


Soil  Report  No.  i 


[March, 


in  extent  and  more  frequently  only  a fraction  of  an  acre,  often  occurring  as 
narrow  strips  along  the  stream  or  draw. 

The  total  area  of  yellow-gray  silt  loam  is  21,240  acres,  or  7.09  percent 
of  the  total  area  of  the  county. 

Since  the  type  is  a transitional  form,  between  other  types,  the  surface  soil 
varies  a great  deal.  The  predominating  phase  is  a yellowish  or  grayish 
yellow  silt  loam,  but  the  type  varies  from  that  to  a gray  silt  loam  as  it 
grades  toward  the  gray  and  the  light  gray  silt  loam  on  tight  clay  (330  or 
332),  or  to  yellow  silt  loam  as  it  passes  into  the  eroded  type  (335). 

In  physical  composition,  it  contains  some  fine  sand  and  locally,  in  small 
areas,  quite  appreciable  amounts,  but  the  prominent  constituent  is  silt  of 
various  grades.  The  soil  is  deficient  in  organic  matter,  there  being  only  1^2 
to  2 percent  present.  The  surface  soil  is  porous  and  friable  but  “runs  to- 
gether’’ badly  because  of  its  shortage  in  organic  matter. 

The  subsurface,  like  the  surface,  varies  from  a yellowish  gray  to  yellow 
silt  loam  sufficiently  porous  to  permit  percolation,  and  the  physical  composi- 
tion is  such  as  to  allow  ready  capillary  movement.  The  thickness  of  the 
subsurface  stratum  varies  from  a few  inches  to  about  16  inches. 

The  subsoil  is  a yellow  or  mottled  grayish  silt  or  clayey  silt,  somewhat 
compact  but  pervious.  The  depth  to  the  subsoil  is  quite  variable  owing  to 
the  amount  of  washing  that  has  taken  place.  In  places  the  surface  and  sub- 
surface have  been  entirely  removed,  but  this  is  unusual,  and  the  depth  to  the 
subsoil  varies  commonly  from  10  to  20  inches. 

With  good  farming  and  a liberal  use  of  limestone,  phosphorus,  and  le- 
gumes, this  soil  can  be  profitably  improved  until  it  will  produce  larger  crops 
than  the  present  average  of  the  $200  corn  belt  land,  which,  of  course,  will 
just  as  certainly  lose  its  high  productive  power  if  the  common  agricultural 
practice  of  the  corn  belt  is  continued,  with  no  adequate  return  to  the  soil 
for  the  large  amounts  of  plant  food  removed  in  crops. 

Yellow  Silt  Loam  (335) 

This  type  includes  the  broken,  very  rolling,  and  hilly  land  along  the 
streams  and  sometimes  on  the  steep  slopes  of  ridges.  It  is  of  such  a steeply 
sloping  character  that  much  of  it  should  never  have  been  put  under  cultiva- 
tion. When  properly  treated  it  makes  excellent  pasture  land,  and  much  of 
it  should  be  kept  forested.  When  cultivated  the  utmost  care  should  be  taken 
to  prevent  washing  as  this  is  the  most  serious  danger  to  this  type  of  soil. 
Already  many  fields  have  been  ruined  by  gullying.  In  Clay  County  it  covers 
an  area  of  41,760  acres,  or  14  percent  of  the  total. 

The  surface  soil  is  a friable  yellow  silt  loam  varying  somewhat  with 
topography,  the  less  broken  being  grayish  yellow  while  the  steep  slopes  are 
reddish  yellow,  or  brownish  yellow  where  a little  more  organic  matter  re- 
mains. As  a rule,  the  soil  has  enough  fine  sand  for  fairly  good  texture,  but 
it  is  very  deficient  in  organic  matter  and  this  condition  "contributes  toward 
its  excessive  washing.  “Clay  points”,  or  places  where  the  top  soil  has  been 
removed  by  washing,  are  quite  common  and  they  are  very  unproductive. 

The  subsurface  varies  but  is  from  6 to  14  inches  thick  where  little  or  no 
washing  has  taken  place.  It  consists  usually  of  a friable  yellow  slightly 
loamy  silt  mottled  with  gray  or  with  reddish  blotches  of  iron  oxid. 

The  subsoil  is  usually  a somewhat  friable  and  quite  pervious  yellow  clayey 
silt.  Where  much  washing  has  occurred  the  glacial  drift  frequently  forms 
the  subsoil. 


Clay  County 


29 


1911] 


Where  soil  improvement  is  attempted,  large  use  should  be  made  of  lime- 
stone and  legumes.  Limestone  may  be  applied  as  a top-dressing  even  on 
permanent  pastures,  and  some  clover  can  usually  be  introduced  into  the 
pasture  herbage  by  mixing  the  clover  seed  with  much  limestone  and  some 
dry  soil  containing  clover  bacteria,  and  sowing  with  a sharp  disk  drill  with 
fertilizer  attachment,  thus  placing  the  inoculated  clover  seed  in  the  soil  itself 
and  in  contact  with  the  limestone.  As  a rule  it  is  not  advisable  to  apply  phos^ 
phorus  to  this  soil  except  where  ample  provision  is  made  for  increasing 
the  organic  matter  and  nitrogen  and  for  preventing  loss  by  erosion ; and  the 
phosphorus  should  not  be  used  as  a top-dressing,  but  thoroly  mixed  with  the 
plowed  soil  before  seeding  down  to  grass  and  clover. 


(c)  Ridge  Soils 
Yellow  Silt  Loam  (235) 

The  morainal  and  preglacial  ridges  of  the  lower  Illinoisan  glaciation  have 
given  a slight  variation  to  the  usual  level  topography  of  this  region.  These 
have  been  covered  with  from  8 to  15  feet  of  loess  and  this,  together  with 
the  excellent  drainage,  has  resulted  in  the  formation  of  a soil  very  different 
from  the  surrounding  prairie  but  somewhat  resembling  in  texture  the  better 
phase  of  the  yellow  silt  loam  timber  land  (335),  already  described.  The 
total  area  of  the  type  is  2560  acres.  The  ridges  upon  which  this  type  occurs 
vary  from  20  feet  to  100  feet  or  more  in  height. 

The  surface  soil  is  a yellow  or  yellowish-brown  silt  loam  with  consider- 
able very  fine  sand.  The  color  varies  with  the  amount  of  erosion  that  has 
gone  on.  Where  little  washing  has  occurred  the  color  may  be  a yellowish 
brown,  while  with  more  washing  it  will  become  yellow.  The  soil  is  loose, 
porous,  readily  pervious  to  water  and  its  physical  composition  is  such  as  to 
give  it  great  water-retaining  power  and  strong  capillarity  so  that  it  will  re- 
sist drouth  well.  The  organic  matter  content  is  about  3^  percent. 

The  subsurface  layer,  62/3  to  20  inches,  varies  from  a yellowish  brown 
silt  loam  to  a yellow  silt  or  slightly  clayey  silt.  It  becomes  more  compact 
with  depth  but  still  retains  its  perviousness  and  capillary  power. 

The  upper  part  of  the  subsoil  is  somewhat  compact  and  slightly  clayey 
but  passes  into  a friable  silt  containing  some  fine  sand.  It  is  yellow  or  red- 
dish-yellow  in  color.  Below  24  inches  it  may  be  slightly  gray  or  marked 
with  gray  blotches,  and  when  grading  toward  yellow-gray  silt  loam  (334) 
may  become  decidedly  gray.  This  soil,  considered  from  a physical  standpoint, 
is  about  as  good  as  could  be  desired.  Its  organic  matter  content  should  be 
maintained  and  even  increased  in  order  to  prevent  destructive  washing.  It 
is  a well-aerated,  well-drained  soil  and  will  withstand  drouth  well,  and  in 
those  respects  it  is  decidedly  the  best  upland  type  in  the  county. 

It  also  contains  a fair  amount  of  plant  food,  exceeding  in  its  nitrogen 
content  all  other  upland  types  and  even  the  extensive  bottom  lands  Never- 
theless it  is  plain  to  see  that  nitrogen  and  phosphorus  are  the  limiting  ele- 
ments in  this  as  well  as  in  most  other  soils  of  the  county ; and  with  the 
well  developed  acidity  of  the  subsurface  and  subsoil,  the  essential  require- 
ments  for  its  improvement  are  the  same;  namely,  a liberal  use  of  limestone 
phosphorus,  and  legume  crops  in  a good  rotation,  the  legumes  and  at  least 
the  coarse  product  of  the  other  crops  being  returned  to  the  soil  either  directly 


30 


Soil  Report  No. 


[March, 


or  in  manure.  By  these  means  this  soil  can  readily  be  made  to  produce  crop 
yields  equal  to  those  of  the  best  soils  in  the  state.  It  is  especially  well 
adapted  for  alfalfa  when  well  treated  with  limestone  and  manured  and  in- 
oculated to  give  the  alfalfa  a good  start. 

Gray-red  Silt  Loam  on  Tight  Clay  (233) 

This  type  of  soil  occurs  on  the  low  ridges,  which  are  in  part  at  least  of 
preglacial  origin,  varying  from  5 to  75  feet  above  the  surrounding  upland. 
As  a rule,  it  is  one  of  the  poorest  upland  types  in  the  state,  but  the  areas  in 
this  county  are  usually  a better  phase  of  the  tyfie.  It  comprises  9180  acres, 
or  3 percent  of  the  area  of  the  county.  The  surface  drainage  is  usually  good, 
and  in  some  places  the  type  may  suffer  from  erosion;  but  it  is  extremely 
doubtful  whether  tile-drainage  will  profitably  benefit  this  soil,  at  best  not 
until  other  methods  of  improvement  have  been  put  into  practice. 

The  surface  soil  is  a friable  gray  silt  loam  very  similar  to  that  of  the 
gray  silt  loam  on  tight  clay  (330),  and  the  subsurface  layer  resembles  the 
corresponding  one  in  the  above  type  both  in  texture  and  thickness  but  con- 
tains more  of  the  higher  oxid  of  iron,  giving  it  a reddish  color. 

The  subsoil  varies  in  depth  from  7 to  20  inches  from  the  surface  and 
consists  of  a layer  of  plastic,  gummy,  impervious  red  clay  varying  from  4 
to  12  inches  thick  and  underlain  by  a less  plastic  and  more  silty  stratum. 
When  dry  the  red  clay  becomes  so  hard  that  it  is  next  to  impossible  to  bore 
into  it  with  an  auger.  Where  this  layer  becomes  the  surface  soil,  which  it 
does  on  some  small  eroded  areas,  the  soil  is  practically  worthless. 

In  plant  food  content  this  soil  is  almost  a perfect  duplicate  of  the  gray 
silt  loam  on  tight  clay,  not  only  in  the  surface,  but  likewise  in  the  sub- 
surface and  subsoil ; but  with  its  tighter  texture  and  more  rolling  topog- 
raphy, more  erosion  and  less  leaching  have  occurred,  and  consequently  it 
has  retained  more  acidity  and  somewhat  more  of  the  abundant  mineral  ele- 
ments. Methods  for  improvement  are,  of  course,  the  same  as  for  the  more 
extensive  gray  silt  loam  on  tight  clay. 

(d)  Bottom  Lands 
Deep  Gray  Silt  Loam  ( 1331 ) 

This  type  occurs  along  most  of  the  streams  of  the  lower  Illinoisan  glacia- 
tion. The  material  from  which  it  is  formed  comes  from  the  gray,  yellow- 
grav,  and  yellow  silt  loams  of  the  upland,  and  has  a gray  or  yellowish  gray 
color.  It  overflows  during  floods  and  in  most  places  still  receives  frequent 
or  occasional  deposits  of  new  material.  If  we  disregard  the  difficulties  from 
overflow  and  of  drainage,  this  is  the  most  valuable  important  soil  type  in 
the  county. 

There  is  in  the  county  a total  area  of  31,680  acres  of  this  type.  It  lies 
so  low  that  the  drainage  is  generally  poor  and  there  is  often  much  difficulty 
in  getting  sufficient  outlet  for  under-drainage  or  sometimes  even  for  adequate 
surface  drainage.  Where  a satisfactory  outlet  can  be  secured  tile  drainage 
greatly  benefits  this  soil. 

The  surface  soil  is  a gray  silt  loam  varying  from  a light  drab  to  drab  in 
color  and  from  a loam  to  a clayey  silt  loam  in  physical  composition.  The 
subsurface  and  subsoil  are  about  the  same  as  the  surface  except  lighter  in 


Clay  County 


31 


1911] 


color  and  commonly  a little  more  clayey  with  depth.  In  the  smaller  stream 
bottoms  the  recent  deposits  are  frequently  yellow  and  consequently  there 
may  be  a stratum  of  yellow  on  the  gray  varying  from  a few  inches  to  a foot 
or  more  in  thickness. 

In  phosphorus  content  this  soil  slightly  exceeds  the  most  common  prairie 
soil  of  the  corn  belt,  and  the  porous  subsoil  affords  such  a deep  feeding 
range  that  the  application  of  that  element  is  not  likely  to  give  profitable  re- 
turns, except  where  overflow  is  not  common  and  where  the  soil  has  been 
long  cropped. 

The  soil  is  moderately  acid  and  rather  poor  in  nitrogen,  altho  this  per- 
centage deficiency  is  counterbalanced  to  a large  extent  by  its  'great  depth  and 
porosity. 

While  the  overflow  and  drainage  problems  are  of  first  importance,  where 
these  are  under  sufficient  control  to  permit  of  soil  improvement  the  use  of 
limestone  and  the  addition  of  nitrogenous  organic  matter,  as  by  plowing  un- 
der clover  or  manure,  will  make  this  soil  still  more  productive ; and,  if  pro- 
tected so  as  to  prevent  the  usual  overflow  deposits,  the  addition  of  phos- 
phorus will  ultimately  be  necessary,  and  is  likely  to  be  very  profitable  for 
the  highest  improvement  of  the  soil.  To  illustrate  it  may  be  pointed  out 
that  on  the  University  farm  at  Urbana,  land  which  has  yielded  65  bushels 
of  corn  per  acre  as  a six-year  average,  in  a rotation  of  corn,  oats,  and  clover, 
where  limestone  and  organic  manures  have  been  provided,  has  with  the  addi- 
tion of  phosphorus  made  an  average  of  87  bushels  during-  the  same  years. 
Thus  there  may  be  room  for  phosphorus  “at  the  top”,  even  where  very  sat- 
isfactory yields  may  be  secured  without  its  application  and  where  other 
factors  are  of  first  importance. 

Mixed  Sandy  Loam  (ijdi) 

This  type  occurs  chiefly  in  the  bottom  lands  of  the  smaller  streams  and 
principally  in  the  northwest  part  of  the  county,  where  its  greater  prevalence 
is  probably  due  to  the  presence  in  that  section  of  a deposit  of  sandstone 
which  frequently  outcrops  along-  the  streams.  The  breaking  down  of  this 
sandstone,  together  with  the  small  amount  washed  in  from  the  upland,  fur- 
nishes sufficient  sand  to  form  the  type.  Practically  all  of  it  is  subject  to 
overflow.  It  varies  greatly  in  physical  composition  which  in  places  is  changed 
more  or  less  with  each  flood. 

The  surface  soil  is  a brown,  yellowish  brown,  or  yellowish  gray  sandy 
loam.  It  is  very  pervious  to  water  but  usually  has  enough  of  the  finer  soil 
constituents  to  make  it  sufficiently  retentive  of  moisture  to  grow  good  crops. 
All  grades  of  sand  are  present  but  the  coarse  and  medium  predominate.  In 
small  areas  it  varies  in  physical  composition  from  loam  to  sand.  The  or- 
ganic matter  content  also  varies,  but  averages  about  2p£  percent. 

The  subsurface  is  a sandy  loam,  lighter  in  color  than  the  surface,  often 
becoming  more  sandy  with  depth  and  usually  passing  into  a coarse  yellow 
or  yellowish  gray  sand  subsoil. 

The  content  of  sand  and  the  depth  to  the  sand  subsoil  varies  with  the 
topography,  the  higher  places  being  more  sandy,  while  the  low  areas  are 
more  silty  and  more  variable  in  the  subsoil.  The  soil  is  very  productive  ex- 
cept on  very  sandy  spots,  which  are  sometimes  present  but  not  large  enough 
to  map. 

Because  of  their  open  character  sand  soils  are  aerated  to  much  greater 
depths  than  soils  in  which  silt  or  clay  predominate  and  because  of  this  a much 


32 


Soil  Report  No.  i 


[March,  ign 


larger  amount  of  plant  food  is  made  available  even  though  the  sand  soil  may 
be  no  richer  in  the  important  elements.  Thus  with  the  same  content  of  nitro- 
gen and  phosphorus  as  the  gray  silt  loam  prairie,  the  sand  soil  will  produce 
twice  as  large  crops,  because  the  aeration  and  feeding  range  is  at  least  twice 
as  great.  The  acidity  of  the  sand  soil  is  slight.  Where  it  is  subject  to  fre- 
quent overflow  it  is  doubtful  if  any  applications  will  prove  profitable,  but 
where  overflow  is  not  common  both  limestome  and  manure  may  well  be  used 
in  preparing  the  soil  for  alfalfa  for  which  it  is  well  adapted  if  the  drainage 
is  good. 

Drab  Clay  (1315) 

The  total  area  of  this  type  in  the  county  comprises  25  acres  situated  in 
the  bottom  land  near  the  Little  Wabash  River  in  an  area  adjoining  the  deep 
peat  (1301).  It  is  a common  type  in  old  bayous  along  the  Mississippi,  Kas- 
kaskia,  and  Wabash  Rivers,  occurring  in  the  low,  poorly  drained  areas, 
chiefly  former  stream  channels,  now  partly  filled  with  the  finest  sediment. 
The  surface  soil  is  a dark  drab,  granular,  plastic  clay.  The  subsurface  and 
subsoil  are  lighter  in  color  than  the  surface  but  also  consists  of  plastic  clay. 
The  type  is  difficult  to  work,  especially  if  not  well  drained,  the  common 
condition. 

It  is  a neutral  soil  and  fairly  well  supplied  with  plant  food.  The  one 
area  found  in  the  county  is  only  a few  inches  above  the  usual  level  of  the 
ground  water.  It  has  never  been  cropped  and  probably  never  will  be  unless 
it  is  included  in  some  future  extensive  drainage  district  in  which  the  general 
level  of  the  Little  Wabash  River  should  be  lowered  so  as  to  provide  an  outlet 
for  such  low-lying  bottom  lands. 

Deep  Peat  ( 1301 ) 

This  type  is  found  in  a single  small  area  of  only  15  acres  where  springs 
abound  (Section  3,  Township  3,  Range  8),  and  the  type  represents  the 
accumulation  of  vegetation  formed  by  the  growth  of  grasses,  sedges,  mosses 
and  other  plants.  The  surface  of  the  peat  is  only  a few  inches  above  the 
water  level,  and  as  an  outlet  for  adequate  drainage  could  be  provided  only 
at  great  expense  (or  in  connection  with  an  extensive  drainage  system),  the 
utilization  of  this  area  for  anything  but  pasture  is  quite  impracticable  at 
present.  The  samples  show  considerable  carbonate  present,  principally  as 
fragments  of  shells. 

This  soil  contains  about  50  percent  of  organic  matter  and  more  than  20  * 
percent  of  limestone.  If  it  could  be  obtained  in  dry  condition  so  as  to  reduce 
the  expense  of  hauling,  it  could  be  used  with  some  profit  as  a fertilizer  on 
the  acid  upland  soils  in  the  neighborhood,  which,  as  a rule,  are  also  markedly 
deficient  in  nitrogen  and  organic  matter.  The  addition  of  a small  applica- 
tion of  manure  or  some  clover  turned  under  would  hasten  the  decomposition 
of  the  peaty  material  and  thus  greatly  increase  its  value  when  used  as  a fer- 
tilizer. (It  should  be  noted  that  the  specific  gravity  of  peat  soil  is  only 
about  one-half  that  of  normal  soil;  and  consequently  an  acre  of  peat  soil 
6^3  inches  deep  weighs,  in  the  dry  condition,  1 million  pounds,  while  ordi- 
nary soils  weigh  2 million  pounds  for  the  same  stratum.) 


UNIVERSITY  OF  ILLINOIS 


Agricultural  Experiment  Station 


SOIL  REPORT  NO.  2 


MOULTRIE  COUNTY  SOILS] 


By  CYRIB  G.  HOPKINS,  J.  G.  MOSIER, 
J.  H.  PETTIT,  and  J.  E.  READHIMER 


URBANA,  ILLINOIS,  JUNE,  1911 


State  Advisory  Committee  on  Soil  Investigations 

Ralph  Allen,  Delavah 

F.  I.  Mann,  Gilman 

A.  N.  Abbott,  Morrison 

J.  P.  Mason,  Elgin 

E.  W.  Burroughs,  Edwardsville 

Agricultural  Experiment  Station  Staff  on  Soil  Investigations 
Eugene  Davenport,  Director 

Cyril  G.  Hopkins,  Chief  in  Agronomy  and  Chemistry 
Soil  Survey — 

J.  G.  Mosier,  Assistant  Chief 
A.  F.  Gustafson,  Assistant 
C.  C.  Logan,  Assistant 
S.  V.  Holt,  Assistant 
H.  W.  Stewart,  Assistant 
H.  C.  Wheeler,  Assistant 

Soil  Analysis — 

J.  H.  Pettit,  Assistant  Chief 
E.  VanAlstirie,  Assistant 
J.  P.  Aumer,  Assistant 
Gertrude  Niederman,  Assistant 
1 W.  H.  Sachs,  Assistant 
Frances  D.  Abbott,  Assistant 
W.  R.  Leighty,  Assistant 

Soil  Experiment  Fields — 

J.  E.  Readhimer,  Superintendent 
Wm.  G.  Eckhardt,  Assistant 
O.  S.  Fisher,  Assistant 
J.  E.  Whitchurch,  Assistant 
E.  E.  Hoskins,  Assistant 


MOULTRIE  COUNTY  SOILS 


By  CYRIL,  G.  HOPKINS,  J.  G.  MOSIER,  J.  H.  PETTIT,  and  J.  E.  READHIMER 


Introduction 

About  two-thiras  of  Illinois  lies  in  the  corn  belt,  where  most  of  the 
prairie  lands  are  black  or  dark  brown  in  color.  In  the  southern  third  of 
the  state  the  prairie  soils  are  largely  of  a gray  color,  and  this  region  is 
better  known  as  the  wheat  belt,  altho  wheat  is  often  grown  in  the  corn 
belt  and  corn  is  also  a common  crop  in  the  wheat  belt. 

Moultrie  County,  representing  the  corn  belt ; Clay  County,  which  is 
fairly  representative  of  the  wheat  belt ; and  Hardin  County,  which  is  taken 
to  represent  the  unglaciated  area  of  the  extreme  southern  part  of  the  State, 
have  been  selected  for  the  first  Illinois  Soil  Reports  by  counties.  While 
subsequent  County  Soil  Reports  will  be  sent  only  to  the  residents  of  the 
county  concerned  (and  to  anyone  else  upon  request),  these  first  three  are 
sent  to  the  Station’s  entire  mailing  list  within  the  State. 

Each  county  report  is  intended  to  be  as  nearly  complete  in  itself  as  it 
is  practicable  to  make  it,  and  even  at  the  expense  of  some  repetition,  each 
will  contain  a general  discussion  of  important  fundamental  principles  to 
help  the  farmer  and  landowner  to  understand  the  meaning  of  the  soil  fer- 
tility invoice  for  the  lands  in  which  he  is  interested.  In  Soil  Report  No.  I, 
“Clay  County  Soils,”  this  discussion  serves  in  part  as  an  introduction,  while 
in  this  and  other  reports  it  will  be  found  in  the  Appendix,  but  if  necessar” 
it  should  be  read  and  studied  in  advance  of  the  re-port  proper. 


Soil  Formation 

Moultrie  County  lies  wholly  within  the  Early  Wisconsin  Glaciation,  but 
near  its  southern  border.  While  it  has  no  very  distinct  morainal  ridges,  yet 
the  county  is  covered  to  an  average  depth  of  more  than  200  feet  with  a 
deposit  of  glacial  drift  consisting  generally  of  a mixture  of  clay,  silt, 
sand,  gravel,  and  boulders.  This  drift  consists  of  the  Illinoisan  below  and 
the  Wisconsin  above,  separated  by  the  Iowan  loess  carrying  the  old  Sanga- 
mon soil.  Covering  the  Wisconsin  drift  to  a depth  of  three  to  six  feet  or 
more  is  another  layer  of  fine-grained,  loessial  or  wind-blown  material  from 
which  the  present  soil  has  been  formed.  This  has  been  modified  to  a con- 
siderable degree  by  different  conditions  and  agencies,  such  as  the  growth 
of  grasses,  of  timber,  washing  and  drainage,  which  have  given  rise  to  the 
different  soil  types  found  in  the  county. 


3 


4 


Soil  Report  No.  2 


[June, 


Table  1.— Soil  Types  of  Moultrie  County 


Soil 

Type 

No. 

Names 

Area 

in 

sq.  mi. 

Area 

in 

acres 

Percent 

of 

total 

1126 

(a)  Upland  Prairie  Soils  (Page  20) 

Brown  silt  loam 

264.42 

169,229 

77.52 

1120 

Black  clay  loam 

15.42 

9,869 

4.52 

1132 

(b)  Upland  Timber  Soils  (Page  23) 

Light  gray  silt  loam  on  tight  clay 

4.75 

3,040 

1.39 

1134 

Y ellow-gray  silt  loam  

'35.05 

22,432 

10  28 

1135 

Yellow  silt  loam 

2.19 

1,402 

.64 

1454 

(c)  Swamp  and  Bottom-land  Soils  (Page  25) 
Mixed  loam 

13.72 

8,781 

4.02 

1554.6 

(d)  Terrace  Soil  (Page  26) 

Mixed  loam  over  sand  or  gravel 

5.51 

3,526 

1.61 

Totals 

341.06 

218,279 

100.00 

The  only  soil  type  in  the  county  which  includes  non-tillable  land  is  the 
yellow  silt  loam,  whose  topography  is  often  so  steeply  sloping  that  it  ought 
to  be  kept  in  forest  or  at  least  almost  continuously  in  pasture.  Of  course, 
much  of  the  swamp  and  bottom  land  needs  more  adequate  drainage,  which 
is  very  difficult,  if  not  impracticable,  to  provide  as  yet  in  some  places. 


THE  INVOICE  AND  INCREASE  OF  FERTILITY  IN  MOULTRIE 
COUNTY  SOILS 

Soil  Analysis 

In  order  to  avoid  complication  and  confusion  in  the  practical  application 
of  the  technical  information  contained  in  this  report,  the  results  are  given 
in  the  most  simplified  form.  The  composition  reported  for  a given  soil 
type  is  as  a rule  the  average  of  many  analyses,  which,  like  most  things  in 
nature,  show  more  or  less  variation.  For  all  practical  purposes  the  average 
is  most  trustworthy  and  sufficient,  as  will  be  seen  from  Bulletin  123,  which 
reports  the  general  soil  survey  of  the  state,  and  in  which  are  reported  many 
hundred  individual  analyses  of  soil  samples  representing  twenty-five  of  the 
most  important  and  most  extensive  soil  types  in  the  state. 

The  chemical  analysis  of  the  soil  gives  the  invoice  of  fertility  actually 
present  in  the  soil  strata  sampled  and  analyzed,  but  the  rate  of  liberation  is 
governed  by  many  factors,  as  explained  in  the  Appendix.  As  there  stated, 
probably  no  agricultural  fact  is  more  generally  known  by  farmers  and  land- 
owners  than  that  soils  differ  in  productive  power.  Even  though  plowed  alike 
and  at  the  same  time,  prepared  the  same  way,  planted  the  same  day  with  the 
same  kind  of  seed,  and  cultivated  alike,  watered  by  the  same  rains  and 
warmed  by  the  same  sun,  nevertheless  the  best  acre  may  produce  twice 
as  large  a crop  as  the  poorest  acre  on  the  same  farm,  if  not,  indeed,  in  the 
same  field ; and  the  fact  should  be  repeated  and  emphasized  that  the  produc- 
tive power  of  normal  soil  in  humid  sections  depends  primarily  upon  the 
stock  of  plant  food  contained  in  the  soil  and  upon  the  rate  at  which  it  is 
liberated. 


i-iOz 


AAMILOD  moovk 


AXMIIOO  MODVJNT 


AX  Ml  1 1 


K£2z 

COUES  COUNTY 

9 


VM 


SOIL  SURVEY  MAP  OF  MOULTRIE  COUNTY 
UNIVERSITY  OF  ILLINOIS  AGRICULTURAL  EXPERIMENT  STATION 


Moultrie  County 


5 


1911} 


The  fact  may  be  repeated,  too,  that  crops  are  not  made  out  of  nothing. 
They  are  composed  of  ten  different  elements  of  plant  food,  every  one  of 
which  is  absolutely  essential  for  the  growth  and  formation  of  every  agri- 
cultural plant.  Of  these  ten  elements  of  plant  food,  only  two  (carbon  and 
oxygen)  are  secured  from  the  air  by  all  plants,  only  one  (hydrogen)  from 
water,  and  seven  from  the  soil,  altho  nitrogen,  one  of  these  seven  elements 
secured  from  the  soil  by  all  plants  may  also  be  secured  from  the  air  by 
one  class  of  plants  (legumes),  in  case  the  amount  liberated  from  the  soil 
is  insufficient;  but  even  these  plants  (which  include  only  the  clovers,  peas, 
beans,  and  vetches  among  our  common  agricultural  plants)  secure  only  from 
the  soil  six  elements  (phosphorus,  potassium,  magnesium,  calcium,  iron 
and  sulfur)  and  also  utilize  the  soil  nitrogen  so  far  as  it  becomes  soluble 
and  available  during  their  period  of  growth. 

Table  A,  in  the  Appendix,  shows  the  requirements  of  large  crops  for  the 
five  most  important  plant  food  elements  which  the  soil  must  furnish.  (Iron 
and  sulfur  are  supplied  normally  in  sufficient  abundance,  compared  with-  the 
amounts  needed  by  plants,  so  tha-t  they  are  not  known  ever  to  limit  the 
yield  of  crops.) 

In  Table  2 is  recorded  the  invoice  of  the  plowed  soil,  showing  the  total 
amounts  of  these  five  elements  of  plant  food  contained  in  each  of  the  dif- 
ferent types  of  soil  in  Moultrie  County. 


Table  2 Fertility  in  the  Soils  oe  Moultrie  County,  Illinois 

Average  pounds  per  acre  in  2 million  pounds  of  surface  soil  (about  0 to  6%  inches) 


Soil 

Total 

Total 

Total 

Total 

Total 

Total 

Lime- 

Lime- 

type 

Soil  type 

organic 

nitro- 

phos- 

potas- 

magne- 

calci- 

stone 

stone 

No. 

carbon 

gen 

phorus 

sium 

sium 

um 

present 

required 

Upland  Prairie  Soils 


1126 

Brown  silt  loam 

52260 

4810 

980 

36020 

8650 

10430 

8T 

1120 

Black  clay  loam 
(normal  phase) . 

72280 

6480 

1810 

35260 

14830 

20460 

8350 

1120 

Black  clay  loam 
(lighter  phase) . 

52600 

6940 

1320 

32120 

15080 

18560 

760 

Upland  Timber  Soils 


1132 

Light  gray  silt 

loam  on 

tight  clay 

19810 

1680 

600 

35080 

6350 

7390 

120 

1134 

Yellow  gray 

silt  loam 

28170 

2310 

680 

36150 

6040 

6370 

180 

1135 

Yellow  silt  loam 

19260 

1580 

480 

36960 

6220 

5180 

320 

Swamp  and  Bottom-land  Soils 


1454 

Mixed  loam 

(normal  phase) 

41940 

4180 

1260 

41740 

9820 

13000 

780 

1454 

Mixed  loam 
(lighter  phase) 

24420 

2600 

620 

37040 

8520 

13000 

7780 

Terrace  Soil 


Mixed  loam 

over  sand  or 
gravel  .... 

11940 

1300 

500 

34860 

5460 

6300 

These  data  represent  the  total  amounts  of  plant  food  found  in  two 
million  pounds  of  the  surface  soil,  which  corresponds  to  an  acre  of  soil  about 
6%  inches  deep,  including  at  least  as  much  soil  as  is  ordinarily  turned  with 


6 


Soil  Report  No.  2 


[June, 


the  plow,  and  representing  that  part  of  the  soil  with  which  we  incorporate 
the  farm  manure,  limestone,  phosphate,  or  other  fertilizer  applied  in  soil 
improvement.  This  is  the  soil  stratum  upon  which  we  must  depend  in  large 
part  to  furnish  the  necessary  plant  food  for  the  production  of  the  crops 
grown,  as  will  be  seen  from  the  information  given  in  the  Appendix.  Even 
a rich  subsoil  has  little  or  no  value  if  it  lies  beneath  a worn-out  surface, 
but  if  the  fertility  of  the  surface  soil  is  maintained  at  a high  point  then  the 
strong  and  vigorous  plants  will  have  power  to  secure  more  plant  food  from 
the  subsurface  and  subsoil  than  would  be  the  case  with  weak,  shallow- rooted 
plants. 

By  easy  computation  it  will  be  found  that  the  most  common  prairie  soil 
of  Moultrie  County  does  not  contain  enough  total  nitrogen  in  the  plowed 
soil  for  the  production  of  maximum  crops  for  ten  rotations;  while  the  up- 
land timber  soils  contain  as  an  average  less  than  one  half  as  much  nitrogen 
as  the  prairie  land. 

Practically  the  same  condition  obtains  with  respect  to  phosphorus,  nine- 
tenths  of  the  soil  area  of  the  county  containing  no  more  of  that  element 
than  would  be  required  for  twelve  crop  rotations  if  such  crop  yields  were 
secured  as  suggested  in  Table  A of  the  Appendix;  and  in  case  of  the  cereals 
it  will  be  seen  that  about  three-fourths  of  the  phosphorus  taken  from  the 
soil  is  deposited  in  the  grain,  while  only  one-fourth  remains  in  the  straw 
or  stalks. 

On  the  other  hand,  the  potassium  is  sufficient  for  2,800  years,  if  only 
the  grain  is  sold,  or  for  450  years  even  if  total  crops  were  removed  and 
nothing  returned.  The  corresponding  figures  are  about  2,100  and  500  years 
for  magnesium,  and  about  10,000  and  250  years  for  calcium. 

Thus,  when  measured  by  the  actual  crop  requirements  for  plant  food, 
potassium  is  no  more  limited  than  magnesium  and  calcium  and,  as  explained 
in  the  Appendix,  with  these  elements  we  must  also  consider  the  heavier  loss 
by  leaching. 

These  general  statements  relating  to  the  total  quantities  of  plant  food 
in  the  plowed  soil  certainly  emphasize  the  fact  that  the  supplies  of  some  of 
these  necessary  elements  of  fertility  are  extremely  limited  when  measured 
by  the  needs  of  large  crop  yields  for  even  one  or  two  generations  of  people. 

The  variation  among  the  different  soil  types  with  respect  to  their  content 
of  important  plant  food  elements  is  also  very  marked.  Thus,  the  prairie 
soils  contain  from  three  to  four  times  as  much  nitrogen  as  the  timber  lands 
of  the  same  topography ; and  the  normal  black  clay  loam,  the  richest  prairie 
land,  contains  about  three  times  as  much  phosphorus  as  the  upland  timber 
soils. 

On  the  other  hand,  the  most  significant  fact  revealed  by  the  investiga- 
tion of  Moultrie  County  soils  is  the  low  phosphorus  content  of  the  common 
brown  silt  loam  prairie,  a type  of  soil  which  covers  more  than  three-fourths 
of  the  entire  county.  The  market  value  of  this  land  is  about  $200  an  acre, 
and  yet  an  application  of  $30  worth  of  fine-ground  raw  rock  phosphate 
would  double  the  phosphorus  content  of  the  plowed  soil.  Such  an  applica- 
tion properly  made  would  also  double  the  yield  of  clover  in  the  near  future ; 
and,  if  the  clover  were  then  returned  to  the  soil  either  directly  or  in  farm 
manure,  the  combined  effect  of  the  phosphorus  and  nitrogenous  organic 
matter  with'  a good  rotation  of  crops  would  soon  double  the  yield  of  com 
on  most  farms. 


Moultrie  County 


7 


jp/j] 


The  average  yield  of  corn  of  Moultrie  County  for  the  ten  years,  1901 
to  1910,  is  34.7  bushels  per  acre;*  yet  this  county  occupies  the  most  favored 
position  in  the  most  southern  lobe  of  the  corn  belt  of  the  United  States. 
Meanwhile,  Boone  County,  or  the  Wisconsin  line,  nearly  200  miles  farther 
north,  has  averaged  40.5  bushels  of  corn  per  acre  during  the  same  ten  years. 

With  nearly  5,000  pounds  of  nitrogen  in  the  soil  and  an  inexhaustible 
supply  in  the  air,  with  36,000  pounds  of  potassium  in  the  same  soil  and  with 
practically  no  acidity,  the  economic  loss  of  farming  such  land  with  less 
than  1,000  pounds  of  total  phosphorus  in  the  plowed  soil  can  only  be  ap- 
preciated by  the  man  who  fully  realizes  that  the  crop  yields  could  be  doubled 
by  adding  phosphorus, — and  without  change  of  seed  or  season  and  with 
very  little  more  work  than  is  now  devoted  to  the  fields. 

Fortunately,  some  definite  field  experiments  have  already  been  conducted 
on  this  same  type  of  soil  in  different  counties  in  the  same  soil  area  as 
Moultrie  (the  Early  Wisconsin  Glaciation),  as  at  Urbana  in  Champaign 
County,  at  Sibley  in  Ford  County,  and  at  Bloomington  in  McLean  County. 


Results  of  Field  Experiments  at  Urbana 

A three-year  rotation  of  corn,  oats,  and  clover  was  begun  on  the  North 
Farm  at  the  University  of  Illinois  in  1902,  on  three  fields  of  typical  brown 
silt  loam  prairie  land  which,  after  twenty  years  or  more  of  pasturing,  had 
grown  corn  in  1895,  1896  and  1897  (when  careful  records  were  kept  of  the 
yields  produced),  and  had  then  been  cropped  with  clover  and  grass  on  one 
field,  oats  on  another,  and  oats,  cowpeas  and  corn  on  the  third  field,  till  1901. 

As  an  average  of  the  three  years,  1902-1904,  phosphorus  increased  the 
crop  yields  per  acre  by  .68  ton  of  clover,  8.8  bushels  of  corn,  and  1.9  bushels 
of  oats. 

During  the  second  three  years,  1905-1907,  phosphorus  produced  average 
increases  of  .79  ton  of  clover,  13.2  bushels  of  corn,  and  11.9  bushels  of  oats. 

The  third  course  of  the  rotation,  1908-1910,  the  average  increases  produced 
by  phosphorus  were  1.05  tons  of  clover,  18.7  bushels  of  corn,  and  8.4  bushels 
of  oats. 

For  convenient  reference  the  results  are  summarized  in  Table  3. 


Table  3. — Fffect  of  Phosphorus  on  Brown  Silt  Loam 
(Average  increase  per  acre) 


Rotation 

Years 

Corn 

| Oats 

Clover 

tons 

Value  of 
increase 

' Cost  of 
treatment* 

Bus: 

hels 

First 

1902,  3,  4 

8.8 

1.9 

.68 

$ 7.73 

$7.50 

Second  

1905,  6,  7 

13.2 

11.9 

.79 

12.93 

7.50 

Third 

1908,  9,  10 

18.7 

8.4 

1.05 

15.37 

7.17 

*Prices  used  are  35  cents  a bushel  for  corn,  30  cents  for  oats,  $6.00  a ton  for  clover 
hay,  10  cents  and  3 cents  a pound  for  phosphorus  in  bone  meal  and  rock  phosphate,  re- 
spectively. 


As  an  average  the  well  treated  land  has  produced  about  90  bushels  of 
corn,  60  bushels  of  oats,  and  2^/2  tons  of  hay  per  acre.  These  crops  would 
remove  about  130  pounds  of  phosphorus  in  the  nine  years,  while  300  pounds 


*Statistical  Report,  Illinois  State  Board  of  Agriculture,  December  1,  1910,  page  '39. 


8 


Soil  Report  No.  2 


[June, 


Plate  1.  Corn  on  Urban  a experiment  field 
Legume  crops  and  crop  residues  plowed  under 
Limestone  applied 

were  applied  (in  bone  meal  and  in  rock  phosphate,  as  explained  below),  so 
that  the  average  phosphorus  content  of  the  plowed  soil  has  been  increased 
from  about  1,100  in  1901  to  1,300  pounds  per  acre  in  1910,  about  30 
pounds  having  been  returned,  as  an  average,  in  the  organic  manures  described 
below. 

Meanwhile  the  untreated  land  has  lost  about  100  pounds  of  phosphorus, 
corresponding  to  a reduction  from  1,100  to  1,000  pounds. 

As  shown  in  Table  3,  the  phosphorus  paid  its  cost  the  first  rotation, 
and  the  third  rotation  it  paid  more  than  twice  its  cost,  besides  leaving  the 
treated  soil  about  one-third  richer  in  phosphorus  than  the  untreated  soil. 

During  the  first  six  years,  1902-1907,  phosphorus  was  applied  at  the  rate 
of  25  pounds  per  acre  per  annum  in  200  pounds  of  steamed  bone  meal,  600 
pounds  of  bone  usually  being  applied  once  every  three  years  on  the  clover 
sod  and  plowed  under  for  corn.  For  the  last  rotation,  1908-1910,  the  600 
pounds  of  steamed  bone  were  applied  on  one-half  of  each  plot,  and  1,800 
pounds  of  fine-ground  raw  rock  phosphate  on  the  other  half.  The  bone 


I9IJ] 


Moultrie  County 


9 


Plate  2.  Corn  on  Urbana  experiment  field 
IfEGUME  CROPS  AND  CROP  RESIDUES  PLOWED  UNDER 

Limestone  and  phosphorus  applied 

costs  about  $25  a ton  (10  cents  a pound  for  250  of  phosphorus),  and  the 
raw  phosphate  about  $7.50  per  ton  (3  cents  a pound  for  250  of  phosphorus). 

As  an  average  of  the  last  three  years  one  dollar  invested  has  paid  back 
$2.38  from  bone  meal  and  $2.39  from  raw  rock  phosphate  in  the  value  of 
the  increase ; and,  of  course,  the  reserve  supply  of  phosphorus  is  much 
greater  where  the  rock  phosphate  is  used. 

In  1910  the  respective  increases  in  yield  from  bone  meal  and  rock 
phosphate  were  15.2  and  19.6  bushels  of  corn,  11.9  and  12.8  bushels  of  oats, 
and  1.33  and  1.37  tons  of  clover  hay,  the  larger  increase  being  produced  by 
the  raw  rock  phosphate  with  every  crop,  in  harmony  with  the  cumulative 
effect  to  be  expected  from  the  increasing  store  of  phosphorus  in  the  soil. 

As  a rule,  each  increase  given  in  Table  3 represents  the  average  of  dupli- 
cate tests  over  a period  of  three  years.  These  averages  are  considered! 
trustworthy,  excepting,  perhaps,  some  results  on  oats,  due  to  abnormal 
seasons.  Normally  the  oat  crop  shows  a gradually  increasing  effect  from  the 
use  of  phosphorus.  (The  increase  for  oats  in  1910  was  13.8  bushels  in 
grain  farming  and  11  bushels  in  live-stock  farming.) 


10 


Soil  Report  No.  2 


[June, 


Plate  3.  Clover  on  Urbana  experiment  field 

LEGUME  CROPS  AND  CROP  RESIDUES  PLOWED  UNDER 

Limestone  applied 


The  duplicate  tests  each  year  correspond  to  the  two  systems  of  farming 
adopted  on  these  fields,  one  of  which  is  a grain  system  in  which  the  nitrogen 
and  organic  matter  are  maintained  or  increased  by  returning  to  the  land 
all  crop  residues  left  after  the  grain  or  seed  is  sold.  These  residues  include 
the  corn  stalks,  straw,  and  all  clover  except  the  seed.  This  system  in 
complete  form  has  been  practiced  only  during  the  last  three  years,  1908- 
1910,  and  consequently  corn  has  not  yet  been  grown  on  land  where  the  corn 
stalks  had  been  returned  to  the  soil. 

In  the  other  system,  known  as  live-stock  farming,  the  crops  are  all 
harvested  and  used  for  feed  and  bedding,  and  as  many  tons  of  average 
manure  are  applied  as  the  total  number  of  tons  of  air-dry  produce  from  the 
respective  plots.  This  system  in  complete  form  has  been  followed  only  dur- 
ing the  last  six  years,  1905- 1910. 

By  computation  from  data  reported  in  the  Appendix,  it  can  be  determined 
that  about  twice  as  much  phosphorus  leaves  the  farm  in  grain  farming  as  in 
live-stock  farming;  and,  in  consequence,  it  is  to  be  expected  that  the  ap- 
plication of  phosphorus  will  produce  greater  effects  in  the  grain-farming 
system  than  in  live-stock  fanning. 

Table  4 contains  more  complete  data  for  the  corn  crops  grown  on  these 
fields,  including  die  average  yields  o.  1895-1897,  before  any  treatment  was 
applied.  (For  full  entails,  see  Bulletin  125.) 

It  should  be  noted  that  .10  manure  was  applied  during  the  first  rotation, 
1902-1904;  and  that  crop  residues  have  been  returned  only  during  the  last 
rotation,  1908-1910.  (On  plots  2,  4,  6,  an'  C some  legume  catch  crops  have 
been  seeded  in  the  corn  at  the  time  of  the  last  cultivation,  but  the  results 
have  not  shown  any  benefit  where  oats  follow  corn,  because  with  a good 
growth  of  corn  the  catch  crop  makes  but  little  growth  the  same  season,  and 
there  is  no  opportunity  for  it  the  following  spring  where  the  land  must  be 
seeded  to  oats.) 


Moultrie  County 


11 


1911] 


Plate  4.  Clover  on  Urbana  experiment  field 

IyEGUME  CROPS  AND  CROP  RESIDUES  PLOWED  UNDER 

Limestone  and  phosphorus  applied 


Table  4 — Average  Corn  Yields  per  Acre  on  Urbana  Experiment  Field, 
On  Common  Corn  Belt  Prairie  Soil:  Brown  Silt  Eoam 


Plot  No. 

1 

2 

3 

4 

5 

6 

7 

8 

9 

Corn,  1895-7 

61.2 

63  4 

61.2 

63.1 

66.1 

65.9 

65.7 

64.0 

65.9 

Plan  of  treat- 
ment partially 
begun,  1902 

None 

Resi- 

dues 

Ma- 

nure 

Resi- 

dues, 

lime 

Ma- 

nure, 

lime 

Residues, 

lime, 

phos- 

phorus 

Manure, 

lime, 

phos- 

phorus 

Residues, 

lime, 

phos- 

phorus, 

potas- 

sium 

Manure, 

lime, 

phos- 

phorus, 

potas- 

sium 

Corn,  1902-4 

75.4 

77.4 

75.3 

78.4 

80.8 

88.0 

88.8 

90.1 

90.5 

Corn,  1905-7 

71.5 

68.5 

80.5 

72.3 

84.8 

90.4 

93.2 

93.8 

95.6 

Corn,  1908-10  .... 

49.4 

51.5 

69.3 

58.1 

74.9 

83.8 

86.6 

86.7 

90.9 

Average  Increase  from  Treatment  Named:  Corn,  bushels 


By  additions 

Resi- 

dues 

Ma- 

nure 

Bime 

Eime 

Phos- 

phorus 

Phos- 

phorus 

Potas- 

sium 

Potas- 

sium 

1902-4;  3 yrs  

1.0 

5.5 

9.6 

8.0 

2.1 

1.7 

1905-7;  3 yrs 

9.0 

3.8 

4.3 

18.1 

8.4 

3.4 

2.4 

1908-10;  3 yrs 

2.1 

19.9 

| 6.6 

5.6 

25. 7 

11.7 

2.9 

4.3 

Even  though  the  grain  system  was  not  fully  underway,  the  organic 
manures,  limestone  and  phosphorus  increased  the  yield  of  corn  by  34.4 
bushels  per  acre  in  grain  farming,  and  by  37.2  bushels  in  live-stock  farming, 
as  an  average  of  the  last  three  years. 

Wheat  is  grown  on  the  University  South  Farm,  in  a rotation  experiment 
started  more  recently.  As  an  average  of  the  last  three  years,  1908-1910, 
raw  rock  phosphate,  (with  no  previous  applications  of  bone  meal)  has 
increased  the  yield  of  wheat  by  8.4  bushels  per  acre,  and  here  too  the 
phosphorus  has  paid  back  more  than  twice  its  cost,  as  an  average  of  the 


12 


Soil  Report  No.  2 


[June, 


Plate  5.  Wheat  in  1911  on  Urbana  field 
Catch  crops  and  crop  residues  plowed  under 
Average  yield,  35.2  bushels  per  acre 

last  three  years,  the  cost  being  $1.87^2,  and  the  value  of  the  increase  $3.81 
per  acre  per  annum,  wheat  being  valued  at  70  cents  a bushel  and  other  crops 
as  noted  above.  (Only  five-sixths  as  muph  rock  phosphate  is  applied  on 
the  South  Farm  as  is  reported  above  for  the  third  rotation  in  the  North 
Farm  experiments,  and  even  this  application  will  be  reduced  one-half  or  more 
after  the  soil  has  become  sufficiently  rich  for  the  production  of  maximum 
crops. ) 

Since  the  above  was  written  the  1911  crop  of  wheat  has  been  harvested 
and  threshed  on  the  University  South  Farm. 

In  the  grain  system  of  farming,  the  yield  was  35.2  bushels  per  acre  where 
catch  crops  and  crop  residues  have  been  plowed  under  without  the  use  of 
phosphorus ; but  where  rock  phosphate  has  been  used  the  average  yield  was 
50.1  bushels  in  the  same  system.  (See  Plates  5 and  6.) 

In  the  live-stock  farming,  the  yield  was  34.2  bushels  where  manure  and 
catch  crops  are  used  without  phosphate,  and  51.8  bushels,  as  an  average, 
where  rock  phosphate  is  used  in  connection  with  the  live-stock  system.  (See 
Plates  7 and  8.) 


Moultrie  County 


13 


J9U\ 


Plate  6.  Wheat  in  1911  ON  Urbana  field 
Catch  crops  and  crop  residues  plowed  under 
Fine-ground  rock  phosphate  applied 
Average  yield,  50.1  bushels  per  acre 

These  results  emphasize  the  cumulative  effect  of  permanent  systems  of 
soil  improvement.  The  value  of  the  increase  produced  by  phosphorus  in 
the  1911  wheat  crop  alone  would  nearly  pay  for  the  cost  of  the  phosphate 
for  eight  years. 

Results  oe  Experiments  on  Sibley  Field 

Table  5 gives  results  obtained  during  the  past  nine  years  from  the 
Sibley  soil  experiment  field,  located  in  Ford  County  on  typical  brown  silt 
loam  prairie  of  the  Illinois  corn  belt. 

Previous  to  1902  this  land  had  been  cropped  with  corn  and  oats  for 
many  years  under  a system  of  tenant  farming  and  the  soil  had  become 
somewhat  deficient  in  active  humus.  While  phosphorus  was  the  limiting 
element  of  plant  food,  the  supply  of  nitrogen  becoming  available  annually 
was  but  little  in  excess  of  the  phosphorus,  as  is  well  shown  by  the  com 
yields  for  1903,  when  phosphorus  produced  an  increase  of  8 bushels,  nitro- 


14 


Soil  Report  No.  2 


[June, 


Plate  7.  Wheat  in  1911  on  Urban  a field 
Catch  crops  and  farm  manure  plowed  under 
Average  yield,  34.2  jushels  per  acre 

gen  without  phosphorus  produced  no  increase,  but  nitrogen  and  phosphorus 
increased  the  yield  by  15  bushels. 

After  six  years  of  additional  cropping,  however,  nitrogen  appears  to  have 
become  the  most  limiting  element,  the  increase  in  1907  being  9 bushels 
from  nitrogen  and  only  5 bushels  from  phosphorus,  while  both  together 
produced  an  increase  of  33  bushels  of  corn.  By  comparing  the  corn  yields 
for  the  four  years,  1902,  1903,  1906  and  1907,  it  will  be  seen  that  the 
untreated  land  has  apparently  grown  less  productive,  whereas  on  land  re- 
•ceiving  both  phosphorus  and  nitrogen  the  yield  has  appreciably  increased, 
so  that  in  1907,  when  the  untreated  rotated  land  produced  only  34  bushels 
•of  corn  per  acre,  a yield  of  72  bushels,  or  more  than  twice  as  much,  was 
produced  where  lime  nitrogep  and  phosphorus  had  been  applied,  althc 
these  two  plots  produced  exactly  the  same  yield  (57  bushels)  in  1902. 

Even  in  the  unfavorable  season  of  1910  the  highest  yielding  plot  ex 
ceeded  that  of  1902,  while  the  untreated  land  produced  less  than  half  as 
much.  Phosphorus  appears  to  have  been  the  first  limiting  element  again 
in  1909  and  1910. 


Moultrie  County 


15 


1911] 


Plate  8.  Wheat  in  1911  ON  Urbana  field 
Catch  crops  and  farm  manure  plowed  under 
Fine-ground  rock  phosphate  applied 
Average  yield,  51.8  bushels  per  acre 

In  the  lower  part  of  Table  5 are  shown  the  total  values  per  acre  of  the 
nine  crops  from  each  of  the  ten  different  plots,  the  amounts  varying  from 
$140.17  to  $214.96;  also  the  value  of  the  increase  produced;  first,  above 
the  untreated  land;  and,  second,  above  the  treatment  with  lime  alone,  com 
being  valued  at  35  c.ents  a bushel,  oats  at  30  cents  and  wheat  at  70  cents. 

Phosphorus  without  nitrogen  produced  $24.44  in  addition  to  the  in- 
crease by  lime;  and  with  nitrogen  phosphorus  produced  $56.14  in  addition  to 
the  increase  by  lime  and  nitrogen,  the  principal  part  of  these  increases  having 
been  made  during  the  later  years. 

The  results  show  that  in  21  cases  out  of  36  the  addition  of  potassium 
decreased  the  crop  yields. 

By  comparing  plots  101  and  102,  and  also  109  and  no,  it  will  be 
seen  that  the  average  increase  by  lime  was  $9.90,  or  more  than  $1.00  an  acre 
a year,  suggesting  that  the  time  is  near  when  limestone  must  be  applied  to 
these  brown  silt  loam  soils. 


16 


Soil  Report  No.  2 


[June, 


Table  5— Crop  Yields  in  Soil  Experiments:— Sibley  Field 


Brown  silt  loam  prairie; 

Corn 

Corn 

Oats 

Wheat 

Corn 

Corn 

Oats 

Wheat 

Corn 

Early  Wisconsin  glaciation 

1902 

1903 

1904 

1905 

1906 

1907 

1908 

1909 

1910 

applied 

Bushels 

per  acre 

101 

None 

57.3 

50.4 

74.4 

29.5 

36.7 

33.9 

25.9 

25.3 

26.6 

lu2 

Lime 

60.0 

54.0 

74.7 

31.7 

39.2 

38.9 

24.7 

28.8 

34.0 

103 

Lime,  nitrogen 

60.0 

54.3 

77.5 

32.8 

41.7 

48  1 

36.3 

19.0 

29.0 

104 

Lime,  phosphorus.. 

61.3 

62.3 

92.5 

36.3 

44.8 

43.5 

25.6 

32.2 

52.0 

105 

Lime,  potassium.  . 

56.0 

49.9 

74.4 

30.2 

37.5 

34.9 

22.2 

23.2 

34.2 

106 

Lime,  nitrogen 

phosphorus. . . . 

57.3 

69.1 

88.4 

45.2 

68.5 

72.3 

45.6 

33.3 

55.6 

107 

Lime,  nitrogen 

potassium  .... 

53.3 

51.4 

75.9 

37.7 

39.7 

51.1 

42.2 

25.8 

46.2 

108 

Lime,  phosphorus 

potassium 

58.7 

60.9 

80.0 

39.8 

41.5 

39.8 

27.2 

28.5 

43.0 

109 

Lime,  nitrogen, 

phosphorus, 

potassium 

58.7 

65.9 

82.5 

48.0 

69.5 

80.1 

52.8 

35.0 

58.0 

110 

Nitrogen, 

phosphorus, 

potassium 

60.0 

60.1 

85.0 

48.5 

63.3 

72.3 

44.1 

30.8 

64.4 

Value  of  Crops  per  Acre  in  Nine  Years 


Plot 

Soil  treatment  applied 

Total  value  of 
nine  crops 

Value  of  increase 

101 

102 

None 

Lime 

$140.17 

151.30 

$11.13 

Over  lime 

103 

Lime,  nitrogen 

151.99 

11.82 

$ .69 

104 

Lime,  phosphorus  . . . 

175.74 

35.57 

24.44 

105 

Lime,  potassium  . . . 

140.73 

.56 

(-10.57) 

106 

Lime,  nitrogen, 

phosphorus  

208.13 

67.96 

56.83 

107 

Lime,  nitrogen, 

potassium 

164.48 

24.31 

13.18 

108 

Lime,  phosphorus, 

potassium 

165.33 

25.16 

14.03 

109 

Lime,  nitrogen, 
phosphorus, 
potassium 

214.96 

74.79 

63.66 

110 

Nitrogen,  phosphorus, 
potassium 

206.28 

66.11 

Results  oe  Experiments  on  Bloomington  Field 

Space  is  taken  to  insert  Table  6,  giving  all  of  the  results  thus  far  obtained 
from  the  Bloomington  soil  experiment  field,  which  is  also  located  on  the 
brown  silt  loam  prairie  soil  of  the  Illinois  corn  belt. 

The  general  results  of  the  nine  years’  work  on  the  Bloomington  field 
tell  the  same  story  as  those  from  the  Sibley  field.  The  rotations  differed 
by  the  use  of  clover  and  by  discontinuing  the  use  of  commercial  nitrogen, 
after  1905,  on  the  Bloomington  field,  in  consequence  of  which  phosphorus 
without  commercial  nitrogen  (Plot  104)  produced  practically  the  same 
increase  ($56.05)  as  was  produced  by  phosphorus  over  nitrogen  on  the 
Sibley  field  (see  Plots  103  and  106). 


Moultrie  County 


17 


1911] 


Table  6 Crop  Yields  in  Soil  Experiments:  Bloomington  Field 


Brown  silt  loam  prairie; 
Early  Wisconsin  glaciation 

Corn 

1902 

Corn 

1903 

Oats 

1904 

Wheat 

1905 

Clover 

1906 

Corn  I 
1907 

Corn 

1908 

Oats 

1909 

Clover 

1910f 

Plot 

Soil  treatment  applied 

Bushels  or  tons  per  acre 

101 

None 

30.8 

63.9 

54.8 

30.8 

.39 

60.8 

40.3 

46.4 

1.56 

102 

Lime 

37.0 

60.3 

60.8 

28.8 

.58 

63.1 

35.3 

53.6 

1.09 

103 

Eime,  nitrogen  

35.1 

59.5 

69.8 

30.5 

.46 

64.3 

36.9 

49.4 

(.83) 

104 

Lime,  phosphorus 

41.7 

73.0 

72.7 

39.2 

1.65 

82.1 

47.5 

63.8 

4.21 

105 

Lime,  potassium  

37.7 

56.4 

62.5 

33.2 

.51 

64.1 

36.2 

45.3 

1.26 

106 

Lime,  nitrogen,  phosphorus 

43.9 

77.6 

85.3 

50.9 

* 

78.9 

45.8 

72.5 

(1.67) 

107 

Lime,  nitrogen,  potassium. 

40.4 

58.9 

66  4 

29.5 

.81 

64.3 

31.0 

51.1 

( -33) 

108 

Lime,  phosphorus, 

potassium 

50.1 

74.8 

70.3 

37.8 

2.36 

81.4 

57.2 

59.5 

3.27 

109 

Lime,  nitrogen,  phosphorus 

potassium 

52.7 

80.9 

90.5 

51.9 

* 

88.4 

58.1 

64.2 

( -42) 

110 

Nitrogen,  phosphorus 

potassium 

52.3 

73.1 

71.4 

51.1 

* 

78.0 

51.4 

55.3 

( -60) 

Value  oe  Crops  per  Acre  in  Nine  Years 


Plot 

Soil  treatment  applied 

Total  value  of 
nine  crops 

Value  of  increase 

101 

102 

None  

Lime 

$132  15 
133.00 

$ .85 

Over  lime 

103 

Lime,  nitrogen  (see  text) 

133.38 

1.23 

$ .38 

104 

Lime,  phosphorus 

189.05 

56.90 

56.05 

105 

Lime,  potassium  

134.24 

2.09 

1.24 

106 

Lime,  nitrogen,  phosphorus 

179.16 

47.01 

46.16 

107 

Lime,  nitrogen,  potassium. 

130.85 

(-1.30) 

(-2.15) 

108 

Lime,  phosphorus, 
potassium 

191.40 

59.25 

58.40 

109 

Lime,  nitrogen,  phosphorus, 
potassium 

183.29 

51.14 

50.29 

110 

Nitrogen,  phosphorus, 
potassium  

166.56 

34.41 

*Clover  smothered  out  by  previous  very  heavy  wheat  crop.  After  the  clover 
hay  was  harvested  all  ten  of  the  plots  were  seeded  to  cowpeas  and  the  crop  was 
plowed  under  later  on  all  plots  as  green  manure  for  the  1907  corn  crop. 

fThe  figures  in  parentheses  represent  bushels  of  clover  seed:  the  others,  tons 
of  clover  hay  (in  two  cuttings)  in  1910. 


It  should  be  stated  that  a draw  runs  near  plot  no  on  the  Bloomington 
field  and  the  crops  on  that  plot  are  sometimes  damaged  by  overflow  or 
imperfect  drainage;  also  that  in  1902  the  stand  of  corn  on  the  Bloomington 
field  was  poor,  though  fairly  uniform.  Otherwise  all  results  reported  ifa 
Tables  5 and  6,  including  more  than  150  tests,  are  considered  reliable,  and 
they  furnish  much  information  and  instructive  comparisons. 

Wherever  nitrogen  was  provided  either  by  direct  application  or  by  the 
use  of  legume  crops  the  addition  of  the  element  phosphorus  produced  very 
marked  increases,  the  average  value  being  $56.10  for  the  nine  years,  or 
$6.23  an  acre  a year.  This  is  $3.73  above  its  cost  in  200  pounds  of  steamed 
bone  meal,  the  form  in  which  it  was  applied  to  these  fields.  On  the  other 


18 


Soil  Report  No.  2 


[June, 


hand,  the  use  of  phosphorus  without  nitrogen  will  not  maintain  the  fertility 
of  the  soil  (see  Plots  104  and  106,  Sibley  field) ; and  a liberal  use  of  clover 
or  other  legumes  is  suggested  as  the  only  practical  and  profitable  method 
of  supplying  the  nitrogen,  the  clover  to  be  plowed  under,  either  directly 
or  as  manure,  preferably  in  connection  with  the  phosphorus  applied,  es- 
pecially if  raw  rock  phosphate  is  used. 

From  the  best  treated  plots  130  pounds  per  acre  of  phosphorus  have 
been  removed  from  the  soil  in  the  nine  crops.  This  is  equal  to  1 1 percent  of 
the  total  phosphorus  contained  in  the  surface  soil  of  an  acre  of  the  untreated 
land.  In  other  words,  if  such  crops  could  be  grown  for  80  years  they  would 
require  as  much  phosphorus  as  the  total  supply  in  the  ordinary  plowed  soil. 
The  results  plainly  show,  however,  that  without  the  addition  of  phosphorus 
such  crops  cannot  be  grown  year  after  year.  The  total  phosphorus  applied 
from  1902  to  1910  amounted  to  225  pounds  per  acre.  Where  no  phosphorus 
was  applied  the  crops  removed  only  90  pounds  of  phosphorus  in  nine  years, 
equivalent  to  only  ?y2  percent  of  the  total  amount  (1,200  pounds)  in  the 
surface  soil  at  the  beginning  (1902). 

The;  Subsurface  and  Subsoil 

In  Tables  7 and  8 are  recorded  the  amounts  of  plant  food  in  the  sub- 
surface and  subsoils,  but  it  should  be  remembered  that  these  supplies  are  of 
little  value  unless  the  top  soil  is  kept  rich.  Probably  the  most  important 
information  contained  in  Tables  7 and  8 is  that  the  upland  timber  soils  are 
more  strongly  acid  in  the  subsurface  and  subsoil  than  in  the  surface,  thus 
emphasizing  the  importance  of  having  plenty  of  limestone  in  the  surface 
soil  to  neutralize  the  acid  moisture  which  rises  from  the  lower  strata  by 


Table  7. — Fertility  in  the  Soils  oe  Moultrie  County,  Illinois 
Average  pounds  per  acre  in  4 million  pounds  of  subsurface  soil  (about  6%  to  20  inches) 


Soil 

Total 

Total 

Total 

Total 

Total 

Total 

Lime- 

Lime- 

Type 

Soil  type 

organic 

nitro- 

phos- 

potas- 

magne- 

cal- 

stone 

stone 

No. 

carbon 

gen 

phorus 

sium 

sium 

cium 

present 

requir’d 

Upland  Prairie  Soils 

1126 

Brown  silt  loam 

67420 

6480 

1590 

72590 

20160 

18170 

140 

1120 

Black  clay  loam 
(normal  phase) . 

71140 

6220 

2650 

72340 

30020 

36350 

237C0 

1120 

Black  clay  loam 
(lighter  phase) . 

30040 

4000 

2000 

65720 

38720 

38480 

82'80 

Upland  Timber  Soils 

1132 

Bight  gray  silt 

loam  on  tight 
clay 

16740 

1840 

920 

70740 

19120 

11240 

4520 

1134 

Y ellow-gray  silt 

loam  

17650 

2040 

1100 

74680 

18530 

10230 

1840 

1*35 

Yellow  silt  loam 

17160 

1720 

1200 

80520 

2S2S0 

8440 

6760 

Swamp  and  Bottom-Land  Soils 


1454 

1454 

Mixed  loam 
| (normal  phase) . 
Mixed  loam 
(lighter  phase) . 

71240 

48680 

| 6240 
5680  | 

2000 

1320 

| 80920 
81840 

I 

[ 21640  | 

20680  | 

28720 

2S0'0 

2200 

1000 

Terrace  Soil 

1554.6 

Mixed  loam  over 
sand  or  gravel 

8960 

1360 

1040 

73720 

15440 

11720 

160 

Moultrie  County 


19 


1911] 

capillary  action  during  periods  of  partial  drouth,  which  are  also  critical 
periods  in  the  life  of  such  plants  as  clover.  Thus,  while  the  common  brown 
silt  loam  prairie  soil  is  practically  neutral,  the  upland  soils  that  are  or 
were  timbered  are  already  in  need  of  limestone  as  a rule;  and,  as  already 
explained,  they  are  much  more  deficient  in  phosphorus  and  nitrogen  than 
the  common  prairie. 

Tabus  8.— Fertility  in  the  Soils  or  Moultrie  County,  Illinois 


Average  pounds  per  acre  in  6 million  pounds  of  subsoil  (about  20  to  40  inches) 


Soil 

Total 

Total 

Total 

Total 

Total 

Total 

Lime- 

Lime- 

Type 

Soil  type 

organic 

Nitro- 

Phos- 

Potas- 

Magne- 

Cal- 

stone 

stone 

No. 

carbon 

gen 

phorus 

sium 

sium 

cium 

present 

requir’d 

Upland  Prairie  Soils 


1126 

1120 

1120 

Brown  silt  loam 
Black  clay  loam 
(normal  phase). 
Black  clay  loam 
(lighter  phase) . 

29180 

39230 

19800 

3720 

3670 

2340 

2230 

3130 

2280 

109670 

112730 

83760 

46360 

50690 

121020 

30790 

72840 

510720 

7860 

126200 

1638120 

Upla 

nd  Timber  Soils 

1132 

Light  gray  silt 

loam  on  tight 

clay 

23280 

2670 

2070 

112380 

46770 

30990 

90 

Y ellow-gray 

1134 

silt  loam 

18510 

2360 

1830 

126570 

41510 

18380 

5480 

1135 

Yellow  silt  loam 

14820 

2100 

2040 

143400 

46200 

16140 

480 

Swamp  and  Bottom-Land  Soils 


1454 

Mixed  loam 
(normal  phase). 

41760 

4500  | 

2160 

| 127020 

34260 

35580 

1020 

1454 

Mixed  loam 
(lighter  phase) . 

39360 

4500 

1920 

1 118200 

28320 

32580 

5340 

Terrace  Soil 


1554.6 

Mixed  loam 

over  sand  or 

gravel 

7980 

1380 

1320 

2580 


101460 


26340 


16740 


20 


Soil  Report  No.  2 


[June, 


INDIVIDUAL  SOIL  TYPES 
(a)  Upland  Prairie  Soils 
Brown  Silt  Loam  (1126) 

This  type  occupies  77.5  percent  of  the  area  of  the  county  or  264.42 
square  miles,  equal  to  169,229  acres.  It  has  been  formed  from  wind- 
blown loessial  material  mixed  with  organic  matter  furnished  by  the  roots 
of  prairie  grasses  that  formerly  grew  on  the  native  prairies.  The  topog- 
raphy varies  from  nearly  flat  to  rolling,  the  larger  part  of  the  type  being 
sufficiently  sloping  to  insure  good  surface  drainage,  while  the  rest  is  in 
good  condition  for  tile  drainage. 

The  surface  soil,  o to  6%  inches,  is  a brown  silt  loam,  but  near  the 
boundaries  it  varies  on  the  one  hand  to  almost  black  as  it  passes  toward 
black  clay  loam,  and  on  the  other  to  a grayish  brown  or  yellowish  brown 
as  it  grades  into  the  timber  types.  It  contains  enough  of  the  coarser  con- 
stituents,, sand  and  coarse  silt,  to  make  it  work  easily,  and  yet  enough 
clay  to  give  stability  to  the  soil.  The  organic  matter  content  varies  from 
3L2  to  5 percent,  the  amount  depending  upon  topography  to  a considerable 
extent.  The  lower  and  more  poorly  drained  areas  permitted  the  accumula- 
tion of  a larger  amount  than  the  higher  land  because  of  ranker  growth 
of  grasses  as  well  as  less  decay  on  account  of  moisture. 

The  thickness  of  the  subsurface  varies  from  7 to  14  inches,  and  in 
color  from  a dark  brown  to  a light  yellowish  brown  silt  loam,  the  color  and 
depth  varying  with  the  topography,  being  lighter  in  color  and  shallower 
on  the  more  rolling  areas. 

The  subsoil  to  a depth  of  40  inches  is  a yellow  clayey  silt  or  silty  clay, 
somewhat  plastic  when  wet.  The  color  is  of  >a  brighter  yellow,  even 
somewhat  reddish,  where  there  has  been  good  surface  drainage,  and  of  a 
pale  yellow,  approaching  an  olive  color,  where  poorly  drained.  In  some  of 
the  rolling  areas  the  loess  deposit  has  been  partly  removed  by  washing,  thus 
bringing  the  glacial  drift  within  40  inches  of  the  surface.  This  is  of 
rare  occurrence  in  Moultrie  County. 

In  the  management  of  this  soil,  one  necessary  thing,  aside  from  proper 
drainage  and  good  tillage,  is  to  keep  it  in  good  physical  condition  or  in  good 
tilth.  It  is  a common  practice  in  the  corn  belt  to  pasture  the  corn  stalks 
during  the  winter  and  often  late  in  the  spring,  so  late  in  fact  that  tramping 
puts  the  soil  in  bad  condition  for  working.  It  is  partially  puddled  and  will 
be  cloddy  as  a result.  If  thus  tramped  in  the  spring,  the  natural  agencies  of 
freezing  and  thawing,  wetting  and  drying,  even  with  the  aid  of  ordinary 
tillage,  fail  to  produce  good  tilth  before  the  crop  is  planted  and  the  latter 
necessarily  suffers.  This  will  be  much  worse  if  the  season  should  be  dry. 
A poor  stand  of  corn  will  result,  if  the  field  is  put  in  corn,  and  a compact 
baked  soil  unfavorable  for  growth,  if  put  in  oats.  Sometimes  farmers  will 
not  wait  for  their  soils  to  become  sufficiently  dry  to  work  well,  and  a 
puddled  soil  results  which  is  very  unfavorable  to  physical,  chemical,  and 
biological  processes.  This  will  be  especially  true  if  cropping  has  reduced 
the  amount  of  organic  matter  below  what  is  necessary  to  maintain  good 
tilth.  Every  practicable  means  should  be  used  to  maintain  the  supply  of 
this  constituent.  Clover  should  be  grown  every  three  or  four  years  and  the 
bulk  of  the  crop  turned  under,  either  directly  or  after  removing  the  seed 


Moultrie  County 


21 


19 II] 

or  after  feeding  and  bringing  back  all  the  manure.  All  straw  should  be 
returned  to  the  land  and  plowed  under  if  not  used  as  bedding  or  fed,  and 
stalks  should  be  chopped  up  and  turned  under  as  well  as  weeds  and  trash. 
In  this  way  only  can  the  present  fair  supply  of  organic  matter  and  its 
accompanying  nitrogen  be  maintained  in  this  soil.  The  supply  of  phos- 
phorus as  shown  by  field  experiment  is  inadequate  for  the  highest  economical 
production,  and  this  should  be  increased  by  turning  under  with  the  clover 
sod  every  three  or  four  years  at  least  one-half  ton  of  rock  phosphate  per 
acre,  and  the  initial  application  may  well  be  a ton  or  more  per  acre. 

On  the  lighter  phase  of  the  type  and  upon  higher  points  of  the  better 
phase,  the  immediate  use  of  ground  limestone  per  acre  (about  two  tons 
every  four  or  five  years)  is  to  be  recommended.  In  the  near  future,  for 
the  continued  successful  growing  of  clover,  alfalfa,  and  other  legumes, 
limestone  will  generally  have  to  be  used  upon  this  type  of  soil. 

Black  Clay  Loam  (1120) 

This  type  of  soil,  commonly  found  in  the  originally  swampy  or  poorly 
drained  areas  of  the  Early  Wisconsin  Glaciation,  is  frequently  called  “gumbo,” 
because  of  its  sticky  character.  Its  formation  in  these  low  places  is  due  to 
the  accumulation  of  organic  matter  and  the  washing  in  of  the  clay  and 
other  fine  material  from  the  slightly  higher  uplands.  On  account  of  the 
good  surface  drainage  that  exists  generally  in  this  county,  the  black  clay 
loam  constitutes  only  4.5  percent  of  the  entire  area,  or  9,858  acres. 

The  topography  of  this  type  is  flat,  yet  for  all  areas  of  black  clay  loam 
sufficient  “outlets”  for  tile  may  be  secured  so  that  good  drainage  is  possible 

The  surface  stratum,  o to  6Ys  inches,  is  a black,  plastic  clay  loam  con- 
taining from  5 to  7 percent  of  organic  matter,  or  from  50  to  70  tons  in  an 
acre.  The  surface  soil  is  naturally  quite  granular  and  consequently  pervious 
to  water.  This  granular  character  is  a very  desirable  property  for  all  soils, 
but  especially  for  heavy  ones.  It  keeps  the  soil  mellow  and  if  the  granules 
are  destroyed  by  working  while  wet  or  by  the  tramping  of  stock,  they  will  be 
formed  again  by  freezing  and  thawing  and  by  moisture  changes  (wetting 
and  drying).  These  produce  slacking,  as  the  process  is  usually  termed. 
If,  however,  the  humus  and  lime  content  become  low,  this  tendency  to 
granulate  grows  less  and  the  soil  becomes  more  difficult  to  work. 

The  subsurface  stratum,  from  10  to  16  inches  thick,  is  about  the  same 
as  the  surface,  except  that  it  becomes  lighter  with  depth  so  that  the  lower 
part  of  this  stratum  may  pass  into  a drab  or  yellowish  silty  clay.  It  is 
pervious  to  water,  due  to  the  jointing  or  checking  produced  by  shrinkage 
in  times  of  drouth. 

The  subsoil  below  20  inches  is  usually  a drab  or  dull  yellow  silty  clay 
but  locally  may  be  a yellow  clayey  silt.  As  a rule  the  subsoil  is  not  so  highly 
colored  as  that  of  the  better  drained  types,  due  to  the  fact  that  the  iron 
is  not  so  highly  oxidized  in  this  poorly  drained  subsoil.  The  subsoil  is 
checked  and  jointed  somewhat  the  same  as  the  subsurface. 

This  type  presents  many  variations.  It  must  be  borne  in  mind  that 
the  boundary  lines  between  different  soil  types  are  not  always  distinct  but 
that  types  frequently  pass  from  one  to  the  other  very  gradually,  thus  giving 
a zone  of  greater  or  less  width  intermediate  between  the  two  types.  The 
black  clay  loam  (1120)  is  usually  surrounded  by  brown  silt  loam  (1126) 


22 


Soil  Report  No.  2 


[June, 


and  it  would  be  expected  that  the  two  would  grade  into  each  other.  This 
gives  variations  including  a lighter  phase  containing  less  of  clay  and  organic 
matter  than  the  average  of  the  type.  In  some  areas  there  has  been  enough 
silty  material  washed  in  from  the  surrounding  higher  land  to  modify  the 
character  of  the  surface  soil.  This  is  true  of  the  Eagle  Pond  district  in 
Sections  14,  23,  24  and  26,  in  Township  14  North,  Range  5 East  of  the 
Third  P.M.,  and  particularly  in  small  areas  surrounded  by  higher  land.  This 
change  is  taking  place  more  rapidly  now  with  annual  cultivation  of  soil 
than  formerly  when  prairie  grass  protected  the  land  from  washing. 

The  amount  of  coarse  soil  constituents,  sand  and  gravel,  varies  in  this 
type.  These  have  been  brought  up  to  some  extent  from  the  underlying 
glacial  drift  by  burrowing  animals,  especially  crayfish,  and  distributed  thru 
the  soil. 

Drainage  is  the  first  requirement  of  this  type,  and  altho  but  very 
slightly  sloping,  yet  this  with  the  perviousness  of  the  soil  gives  an  excellent 
chance  for  surface  and  tile  drainage.  Keeping  the  soil  in  good  physical 
condition  is  very  essential,  and  thoro  drainage  helps  to  do  this  to  a great 
extent.  As  the  organic  matter  is  destroyed  and  the  lime  removed  from  the 
soil,  the  former  by  cultivation  and  decomposition  and  the  latter  by  cropping 
and  leaching,  the  soil  will  attain  a poorer  physical  condition  and  consequently 
become  more  difficult  to  work.  Both  the  organic  matter  and  the  lime  tend 
to  develop  granulation  of  the  soil.  The  former  should  be  maintained  by 
turning  under  manure  or  clover  and  residues  from  crops,  such  as  cornstalks, 
stubble  and  straw,  and  ground  limestone  should  be  applied  where  needed. 

While  this  soil  is  one  of  the  best  in  the  state,  vet  the  clay  and  humus 
which  it  contains  give  it  the  property  of  shrinkage  and  expansion  to  such 
a degree  as  to  be  somewhat  objectionable  at  times.  When  the  soil  is  wet, 
these  constituents  expand,  and  when  the  moisture  evaporates  or  is  used  by 
plants;  the  soil  shrinks.  This  results  in  the  formation  of  cracks  up  to  two 
inches  or  more  in  width  and  extending  with  lessening  width  to  a depth  of 
a foot  or  more.  These  cracks  allow  the  subsoil  to  dry  out  rapidly.  They 
sometimes  “block  out”  the  hills  of  corn  by  cross  cracks,  severing  the  roots 
and  thus  confining  each  hill  to  a comparatively  small  area.  Sometimes 
much  damage  to  the  crop  results.  While  cracking  may  not  be  prevented 
entirely  in  this  type,  yet  it  may  be  controlled  to  some  extent  by  a soil  mulch 
to  check  evaporation  and  prevent  the  cracks  from  extending  to  the  surface. 
Organic  matter,  as  cornstalks  or  straw,  applied  to  the  surface  in  liberal 
amount,  also  makes  a very  Satisfactory  mulch,  but  of  course  this  would 
interfere  with  ordinary  cultivation  and  cropping. 

This  type  of  soil  is  well  supplied  with  organic  matter  and  nitrogen.  It 
has  about  eighty  percent  more  phosphorus  than  does  the  brown  silt  loam  and 
is  abundantly  supplied  with  potassium.  As  a rule,  it  contains  limestone  in 
sufficient  amounts  for  present  use.  Upon  this  soil*  it  is  of  first  importance 
to  establish  a system  which  will  maintain  the  supply  of  actively  decaying 
organic  matter  and  to  so  handle  it  as  to  keep  the  soil  in  good  tilth.  Eventu- 
ally the  use  of  limestone  and  phosphorus  may  be  profitable;  and  on  the 
lighter  phase,  indicated  by  the  lighter  color  and  greater  friability  (because 
of  its  higher  content  of  silt),  applications  of  phosphorus  can  even  now 
be  made  profitable  in  good  systems  of  farming. 


Moultrie  County 


23 


/P'J] 


(b)  Upland  Timber  Soies 
Light  Gray  Silt  Loam  on  Tight  Clay  (1132) 

This  type  comprises  only  1.4  percent  of  the  area  of  the  county  or  3,040 
acres.  It  is  found  almost  entirely  in  the  southern  part  of  the  county  in 
the  timbered  areas  along  the  Kaskaskia  river  and  its  tributaries.  As  a rule, 
it  occurs  in  small,  level,  but  not  swampy  areas  that  have  poor  drainage  on 
account  of  the  topography  and  the  imperviousness  of  the  subsoil.  Practi- 
cally all  of  this  type  is  now  cleared  and  under  cultivation,  but  the  trees 
formerly  growing  upon  it  were  white  oak,  shellbark  hickory,  black  jack 
and  some  post  oak. 

The  surface  soil,  o to  6^3  inches,  is  a light  gray  silt  loam,  incoherent, 
friable,  and  porous.  Iron  concretions,  varying  in  size  from  *4  inch  to 
a pin  head  are  usually  present  in  this  stratum.  The  organic  matter  content 
is  very  low,  being  about  1 *4  per  cent. 

The  subsurface  is  a light  gray  silt  becoming  slightly  yellowish  and  more 
clayey  with  depth. 

The  subsoil  below  20  inches  is  a compact  clayey  silt,  yellow  in  color  with 
gray  or  drab  mottlings.  The  subsoil  below  35  or  40  inches  is  usually 
coarser  and' more  pervious  to  water. 

The  soil  runs  together  after  a rain,  and  limestone  with  organic  matter 
will  prevent  this  to  a very  great  extent. 

Some  carefully  conducted  experiments  are  needed  to  ascertain  the  feasi- 
bility of  tile-drainage  in  this  land. 

In  the  management  of  this  type  the  most  practical  things  to  do  are  to 
apply  limestone  and  phosphorus  and  increase  the  content  of  organic  matter 
in  every  way  practicable.  The  subsoil  is  tight  and  the  growing  of  deep- 
rooting crops  such  as  red,  mammoth,  or  sweet  clover  would  tend  to  make 
it  more  porous  as  well  as  supply  the  soil  with  organic  matter  and  nitrogen. 

Y ellow-Gray  Silt  Loam  (1134) 

This  type  occurs  in  the  timbered  area  along  the  Kaskaskia  river  and  its 
tributaries,  principally  in  the  southern  part  of  the  county,  forming  strips 
along  the  streams  with  a broadening  toward  the  north  and  east  sides  of  the 
streams  where  the  timber  was  protected  from  the  prairie  fires  driven  by  the 
prevailing  south-westerly  winds. 

The  type  occupies  about  10.3  percent  of  the  total  area  of  the  county 
or  22,412  acres,  being  next  in  amount  to  the  brown  silt  loam.  This  type 
is  sufficiently  rolling  for  good  drainage  without  much  tendency  to  wash, 
if  anything  like  proper  care  is  taken  of  the  soil. 

The  surface  soil,  o to  6^3  inches,  Is  a gray  to  yellowish  gray  silt 
loam,  incoherent  and  mealy  but  not  granular.  It  is  low  in  organic  matter 
content,  averaging  about  2^4  per  cent. 

The  characteristic  stratum  in  the  subsurface  varies  from  3 to  10  inches 
in  thickness  and  consists  of  a gray,  grayish  yellow,  or  yellow;  silt  loam, 
somewhat  mealy  but  becoming  more  coherent  and  clayey  with  depth.  Only 
a small  amount  of  organic  matter  is  present. 

The  subsoil  is  a yellow  or  grayish  mottled  yellow  clayey  silt  or  silty 
clay,  somewhat  plastic  when  wet,  but  friable  when  only  moist.  Where 
erosion  has  occurred,  glacial  drift  sometimes  forms  all  or  part  of  the 
subsoil. 


24 


Soil  Report  No.  2 


[June, 


This  type  is  quite  variable,  due  to  the  fact  that  it  grades  into  so  many 
different  types.  It  is  very  probable  that  all  or  very  nearly  all  of  the  tim- 
bered area  was  at  one  time  a part  of  the  prairie  and  the  present  character  of 
the  soil  has  been  produced  by  the  gradual  invasion  and  long  occupancy  of 
forest  growth.  Certain  trees,  such  as  elm,  hard  maple,  wild  cherry,  hack- 
berrv,  and  black  walnut,  were  the  first  to  spread  over  the  prairie.  Long 
periods  (perhaps  thousands  of  years)  were  required  to  produce  much 
change  in  soil.  Other  trees  followed  the  above,  and  the  growth  of  grasses 
to  which  the  accumulation  of  organic  matter  is  largely  due  was  gradually 
diminished  by  shading  and  growth  of  underbrush,  after  which  little  or  no 
organic  matter  was  added  and  incorporated  with  the  soil.  The  leaves  of 
the  trees  falling  upon  the  surface  were  either  burned  or  decayed  completely 
without  being  mixed  with  the  soil  and  gradually  the  organic  matter  content 
was  reduced  until  a gray  silt  loam  or  a yellow-gray  silt  loam  was  the 
result.  There  is  frequently  a zone  of  land  (too  narrow  to  map)  that  repre- 
sents a transition  between  the  brown  silt  loam  and  the  timber  type  in 
which  the  surface  soil  is  brown  or  grayish  brown  and  the  subsurface  is 
grayish  brown  to  gray.  This  gives  a phase  of  the  type  that  is  better  than  the 
average,  especially  as  to  its  content  of  organic  matter. 

The  topography  is  generally  undulating  to  rolling,  becoming  in  some 
places  sufficiently  rolling  so  that  considerable  washing  may  occur  if  not 
properly  managed. 

To  prevent  this  washing,  as  well  as  to  supply  a deficient  and  much 
needed  constituent,  every  practicable  means  should  be  employed  to  increase 
the  oreanic  matter  content  of  this  type.  “Running  together”  is  a fault  of 
this  soil  that  may  thus  be  largely  prevented. 

The  absence  of  limestone  in  the  subsoil  indicates  the  advisability  of 
using  limestone  upon  this  soil  in  order  to  grow  clover,  alfalfa,  and  other 
legumes  more  successfully.  The  soil  is  also  very  deficient  in  phosphorus, 
which  must  be  liberally  supplied  in  any  practicable  system  for  the  marked 
and  profitable  improvement  of  this  soil. 

Yellow  Silt  Loam  (1135) 

This  type  covers  only  1,402  acres,  or  le9s  than  one  percent  of  the  total 
area  of  the  county.  It  occurs  as  narrow  irregular  strips  adjoining  the 
bottom-lands  of  the  Kaskaskia  river,  or  as  arms  projecting  into  other  types 
and  marking  the  location  of  small  streams  that  have  eroded  to  considerable 
depth. 

The  topography  is  very  rolling  to  broken,  so  steep  in  many  places 
that  it  cannot  be  cultivated  and  much  of  it  should  not  be,  because  of 
the  danger  of  injury  from  washing. 

The  surface  soil,  o to  inches,  is  a grayish  yellow,  pulverulent, 

mealy  silt  loam,  somewhat  porous.  'Where  much  recent  washing  has  taken 
place,  the  surface  soil  does  not  differ  materially  from  the  subsoil. 

The  typical  subsurface  varies  considerably,  depending  upon  the  amount 
of  washing  that  has  taken  place.  In  thickness  it  varies  from  o to  12  inches, 
the  variation  being  due  to  the  removal  of  the  surface.  In  fact,  in  many 
places  both  surface  and  subsurface  have  been  removed  exposing  the  subsoil. 

This  latter  consists  of  a compact  yellow  clayey  silt  but  in  places  the 
glacial  drift  may  form  the  whole  or  part  of  the  subsoil,  or  occasionally  it 
may  even  form  the  surface  soil  in  small  patches. 


Moultrie  County 


25 


1911] 

In  the  management  of  this  type  the  chief  thing  is  to  prevent  general 
surface  washing  and  gullying.  If  it  is  cropped  at  all,  a rotation  should  be 
practiced  that  will  require  a cultivated  crop  as  little  as  possible  and  allow 
as  much  pasture  or  meadow  as  possible.  If  tilled,  the  land  should  be  plowed 
deeply  and  contours  should  be  followed  as  nearly  as  possible.  Furrows 
extending  up  and  down  the  slopes  should  be  avoided.  Planting  and  cultiva- 
tion should  be  done  in  the  same  direction  as  plowing.  Every  means  should 
be  employed  to  maintain  and  increase  the  organic  matter  content  to  help 
hold  the  soil  and  keep  it  in  good  physical  condition  so  it  will  absorb  a 
large  amount  of  water  and  thus  diminish  the  run  off.  (See  Circular  119.) 

Limestone  can  be  used  with  profit  on  this  type  of.  soil  where  it  is  to 
be  cropped  or  prepared  for  seeding  down.  Even  top-dressings  of  limestone 
will  usually  help  to  increase  the  leguminous  plants  in  the  herbage  of  perma- 
nent pastures. 

The  application  of  phosphorus  is  not  advised,  unless  special  precautions 
are  taken  to  prevent  surface  erosion;  and,  if  used  at  all,  the  phosphorus 
should  be  mixed  with  the  surface  soil  by  disking  and  then  plowed  under, 
so  as  to  put  the  phosphorus  down  where  the  plant  roots  feed,  and  thus  reduce 
the  danger  of  loss  of  applied  phosphorus  by  erosion. 

(c)  Swamp  and  Bottom-land  Soils 

Bottom-lands  are  usually  named  from  their  distances  above  the  streams 
as  first,  second,  third,  etc.  The  first  bottom  represents  the  flood  plain 
of  the  stream.  The  highest  bottom  is  the  oldest  and  shows  the  height  to 
which  the  old  valley  was  once  filled. 

Mixed  Loam  (1454; 

The  first  bottom  or  overflow  land  along  the  streams  in  the  county  is 
called  mixed  loam.  These  small  bottom  lands  vary  a great  deal  in  the 
kind  of  soil,  and  the  areas  of  these  different  types  are  so  small  that  it  would 
be  entirely  impracticable  to  separate  them.  Moreover,  the  soils  are  changed 
by  floods  so  that  a separation  of  types  would  not  mean  very-  much  after  a 
few  years.  The  total  area  is  only  8,781  acres,  or  a little  more  than  four 
percent  of  the  area  of  the  county. 

The  topography  is  generally  flat,  but  occasionally  an  area  is  found 
that  has  undulating  surface  due  to  the  overflow  stream  channels  that  give 
a little  diversity  to  the  topography. 

The  surface  soil,  o to  inches,  varies  from  a dark  brown  silt  loam, 
or  even  clay  loam,  to  a brown  loam  and  light  brown  sandy  loam.  The 
lower  and  more  nearly  level  areas  are  heaviest  and  blackest  while  the  undulat- 
ing areas  are  more  loamy  and  sandy. 

The  subsurface  soil  is  very  similar  to  but  lighter  in  color  than  the  surface. 
There  is  sometimes  no  distinct  line  separating  the  subsurface  from  the 
subsoil,  the  only  difference  frequently  being  a lighter  color.  In  the  sandy 
areas  the  subsoil  is  generally  more  sandy,  sometimes  becoming  a sand. 

While  the  normal  phase  is  only  moderately  rich  and  the  lighter  phase  is 
rather  low  in  nitrogen  and  phosphorus,  the  soil  is  usually  very  deep  and 
thus  affords  a very  extensive  feeding  range  for  plant  roots.  Drainage  and 
protection  from  overflow  are  the  considerations  of  first  importance  in  dealing 
with  this  soil. 


26 


Soil  Report  No.  2 


[June, 


(d)  Terrace  Soils 

Mixed  Loam  over  Sand  or  Gravel  (1554.6) 

This  type  which  forms  only  1.6  percent  of  the  area  of  the  county,  or 
3,516  acres,  occurs  along  the  Kaskaskia  proper  and  the  West  Fork  of  that 
stream.  The  areas  are  somewhat  isolated  and  represent  an  old  fill  or 
bottom-land  probably  formed  by  the  melting  of  the  Wisconsin  Glacier  at  a 
time  when  the  river  was  overloaded  with  ground-up  material  from  the 
melting  glacier.  The  streams  have  later  cut  down  thru  this  deposit  and 
developed  a new  bottom  that  is  from  10  to  30  feet  below  the  terrace.  Much 
of  the  material  that  , filled  this  old  valley  was  gravel  and  coarse  sand  which 
now  form  the  underlying  stratum  of  this  type.  The  topography  varies  from 
almost  level  to  a gentle  slope  and  in  some  areas  gently  undulating. 

The  surface  soil,  o to  6 2A  inches,  varies  from  a brown  or  yellow  silt 
loam  to  a loam  or  sandy  loam.  The  variations  are  in  too  small  areas  to 
permit  their  being  shown  separately  on  the  map.  As  a general  rule,  there  is 
more  sand  in  the  soil  near  the  first  bottom  than  farther  back.  This  is 
probably  due  to  the  sand  being  blown  up  from  the  lower  bottom-land. 

The  subsurface  stratum  is  from  6 to  12  inches  in  thickness,  being  a 
light  brown  to  yellow  silt  loam  with  variations  of  sand  content  similar  to 
that  of  the  surface  soil. 

The  subsoil  is  a yellow  silt  varying  to  a sandy  silt  or  sandy  loam 
sufficiently  open  and  pervious  to  allow  good  drainage.  Underlying  the 
subsoil  at  a depth  of  from  three  to  six  feet  is  a bed  of  gravel  or  sand  that 
provides  good  underdrainage.  In  dry  seasons  where  the  gravel  is  nearest 
the  surface,  the  crop  may  suffer  from  drouth  because  of  the  inability  of  the 
gravel  to  draw  the  moisture  up  from  below  on  account  of  its  coarseness  and 
consentient  low  capillary  power. 

This  soil  is  one  of  the  poorest  in  the  area  in  phosphorus,  nitrogen,  and 
organic  matter,  thus  resembling  the  yellow  silt  loam,  from  which  it  re- 
ceives some  surface  wash  in  places;  but  its  topography  is  such  as  to  justify 
the  adoption  of  definite  plans  for  improving  this  soil  to  a high  state  of 
productiveness.  Large  use  of  organic  manures  and  liberal  applications  of 
phosphorus  are  the  chief  essentials,  the  addition  of  phosphorus  being  less 
important  on  the  more  sandy  areas,  because  of  the  deep  feeding  range  there 
afforded  for  plant  roots. 

In  places  the  soil  is  acid  and  as  an  average  the  subsurface  and  subsoil 
are  acid.  In  soils  of  such  variable  character  the  landowner  should  thoroly 
test  the  soil  and  subsoil  for  acidity,  using  a few  cents’  worth  of  blue 
litmus  paper  and  following  the  directions  given  in  Circular  no,  “Ground 
Limestone  for  Acid  Soils,”  which  also  contains  directions  for  making  a 
machine  for  spreading  phosphate  and  limestone,  and  will  be  sent  to  any  one 
free  of  charge  upon  application  to  the  Agricultural  Experiment  Station. 


Moultrie  County 


27 


1911] 


APPENDIX 

A study  of  the  soil  map  and  the  tabular  statements  concerning  crop  re- 
quirements, the  plant  food  content  of  the  different  soil  types,  and  the  actual 
results  secured  from  definite  field  trials  with  different  methods  or  systems 
of  soil  improvement,  and  a careful  study  of  the  discussion  of  general  prin- 
ciples and  of  the  descriptions  of  individual  soil  types  will  furnish  the  most 
necessary  and  useful  information  for  the  practical  improvement  and  perma- 
nent preservation  of  the  productive  power  of  every  kind  of  soil  on  every 
farm  in  the  county. 

More  complete  information  concerning  the  most  extensive  and  important 
soil  types  in  the  great  soil  areas  in  all  parts  of  Illinois  is  contained  in  Bulle- 
tin No.  123,  “The  Fertility  in  Illinois  Soils,”  which  contains  a colored  gen- 
eral survey  soil  map  of  the  entire  state. 

Other  publications  of  general  interest  are : 

Bulletin  No.  76,  “Alfalfa  on  Illinois  Soils.” 

Bulletin  No.  94,  “Nitrogen  Bacteria  and  Legumes.” 

Bulletin  No.  99,  “Soil  Treatment  for  the  Lower  Illinois  Glaciation.” 

Bulletin  No.  115,  “Soil  Improvement  for  the  Worn  Hill  Lands  of  Illinois.” 

Bulletin  No.  125,  “Thirty  Years  of  Crop  Rotation  on  the  Common  Prairie  Lands  of 
Illinois.” 

Circular  No.  no,  “Ground  Limestone  for  Acid  Soils.” 

Circular  No.  127,  “Shall  we  use  Natural  Rock  Phosphate  or  Manufactured  Acid  Phos- 
phate for  the  Permanent  Improvement  of  Illinois  Soils  ?” 

Circular  No.  129,  “The  Use  of  Commercial  Fertilizers.” 

Circular  No.  149,  “Some  Results  of  Scientific  Soil  Treatment”  and  “Methods  and  Re- 
sults of  Ten  Years’  Soil  Investigation  in  Illinois.” 

NOTE. — Information  as  to  where  to  obtain  limestone,  phosphate,  bone  meal,  and  po- 
tassium salts,  methods  of  application,  etc.,  will  also  be  found  in  Circulars  no  and  149. 

Soil  Survey  Methods 

The  detail  soil  survey  of  a county  consists  essentially  of  indicating  on 
a map  the  location  and  extent  of  the  different  soil  types;  and,  since  the 
value  of  the  survey  depends  upon  its  accuracy,  every  reasonable  means  is 
employed  to  make  it  trustworthy.  To  accomplish  this  object  three  things  are 
essential : first,  careful,  well-trained  men  to  do  the  work ; second,  an  ac- 
curate base  map  upon  which  to  show  the  results  of  their  work;  and,  third, 
the  means  necessary  to  enable  the  men  to  place  the  soil-type  boundaries, 
streams,  etc.,  accurately  upon  the  map. 

The  men  selected  for  the  work  must  be  able  to  keep  their  location  exactly 
and  to  recognize  the  different  soil  types,  with  their  principal  varieties  and  lim- 
its, and  they  must  show  these  upon  the  maps  correctly.  A definite  system  is 
employed  in  checking  up  this  work.  As  an  illustration,  one  soil  expert  will 
survey  and  map  a strip  80  rods  or  160  rods  wide  and  any  convenient  length, 
while  his  associate  will  work  independently  on  another  strip  adjoining  this 
area,  and,  if  the  work  is  correctly  done,  the  soil  type  boundaries  will  match 
up  on  the  line  between  the  two  strips. 


28 


Soil  Report  No.  2 


[June, 


An  accurate  base  map  for  field  use  is  absolutely  necessary  for  soil  map- 
ping. The  base  maps  are  made  on  a scale  of  one  inch  to  the  mile.  The 
official  data  of  the  original  or  subsequent  land  survey  are  used  as  a basis 
in  the  construction  of  these  maps,  while  the  most  trustworthy  county  map 
available  is  used  in  locating  temporarily  the  streams,  roads,  and  railroads. 
Since  the  best  of  these  published  maps  have  some  inaccuracies,  the  location 
of  every  road,  stream,  and  railroad  must  be  verified  by  the  soil  surveyors, 
and  corrected  if  wrongly  located.  In  order  to  make  these  verifications  and 
corrections,  each  survey  party  is  provided  with  an  odometer  for  measuring 
distances,  and  a plane  table  for  determining  the  directions  of  roads,  rail- 
roads, etc. 

Each  surveyor  is  provided  with  a base  map  of  the  proper  scale,  which  is 
carried  with  him  in  the  field ; and  the  soil-type  boundaries,  additional  streams, 
and  necessary  corrections  are  placed  with  proper  locations  upon  the  map  while 
the  mapper  is  on  the  area.  Each  section,  or  square  mile,  is  divided  into 
40-acre  plots  on  the  map  and  the  surveyor  must  inspect  every  ten  acres  and 
determine  the  type  or  types  of  soil  composing  it.  The  different  types  are 
indicated  on  the  map  by  different  colors,  pencils  being  carried  in  the  field 
for  this  purpose. 

A small  auger  40  inches  long  forms  for  each  man  an  invaluable  tool  with 
which  he  can  quickly  secure  samples  of  the  different  strata  for  inspection. 
An  extension  for  making  the  auger  80  inches  long  is  taken  by  each  party, 
so  that  any  peculiarity  of  the  deeper  subsoil  layers  may  be  studied.  Each 
man  carries  a compass  to  aid  in  keeping  directions.  Distances  along  roads 
are  measured  by  an  odometer  attached  to  the  axle  of  the  vehicle,  while  dis- 
tances in  the  field  off  the  roads  are  determined  by  pacing,  an  art  in  which 
the  men  become  expert  by  practice.  The  soil  boundaries  can  thus  be  lo- 
cated with  as  high  a degree  of  accuracy  as  ^an  be  indicated  by  pencil  on  the 
scale  of  one  inch  to  the  mile. 

Soil  Characteristics 

The  unit  in  the  soil  survey  is  the  soil  type,  and  each  type  possesses 
more  or  less  definite  characteristics.  The  line  of  separation  between  ad- 
joining types  is  usually  distinct,  but  sometimes  one  type  will  grade  into 
another  so  gradually  that  it  is  very  difficult  to  draw  the  line  between  them. 
In  such  exceptional  cases,  some  slight  variation  in  the  location  of  soil-type 
boundaries  is  unavoidable. 

Several  factors  must  be  taken  into  account  in  establishing  soil  types. 
These  are  (1)  the  geological  origin  of  the  soil,  whether  residual,  glacial, 
loessial,  alluvial,  colluvial,  or  cumulose;  (2)  the  topography,  or  lay  of  the 
land;  (3)  native  vegetation,  as  forest  or  prairie  grasses;  (4)  the  structure, 
or  the  depth  and  character  of  the  surface,  subsurface,  and  subsoil;  (5)  the 
physical  or  mechanical  composition  of  the  different  strata  composing  the  soil, 
as  the  percentages  of  gravel,  sand,  silt,  clay,  and  organic  matter  which  they 
contain;  (6)  the  texture,  or  porosity,  granulation,  friability,  plasticity,  etc.; 
(7)  the  color  of  the  strata;  (8)  the  natural  drainage;  (9)  agricultural 
value,  based  upon  its  natural  productiveness;  (10)  the  ultimate  chemical 
composition  and  reaction. 


I9ii] 


Moultrie  County 


29 


The  common  soil  constituents  are  indicated  in  the  following  outline : 


Soil 

Constituents 


Constituents  of  Soils 

Organic  j Comprising  undecomposed  and  partially  decayed 

Matter  j vegetable  material 


Inorganic 

Matter 


f Clay  ooi  mm.*  and  less 

Silt  ooi  mm.  to  .03  mm. 

-j  Sand  03  mm.  to  1.  mm. 

Gravel  1.  mm.  to  32  mm. 

[ Stones  32.  mm.  and  over. 


*25  millimeters  equal  1 inch. 

Further  discussion  of  these  constituents  is  given  in  Circular  82. 


Groups  of  Soil  Types 

The  following  gives  the  different  general  groups  of  soils : 

Peats — Consisting  of  35  percent  or  more  of  organic  matter,  sometimes 
mixed  with  more  or  less  sand  or  silt. 

Peaty  loams — 15  to  35  percent  of  organic  matter  mixed  with  much  sand 
and  silt  and  a little  clay. 

Mucks — 15  to  35  percent  of  partly  decomposed  organic  matter  mixed 
with  much  clay  and  some  silt. 

Clays — Soils  with  more  than  25  percent  of  clay,  usually  mixed  with  much 
silt. 

Clay  loams — Soils  with  from  15  to  25  percent  of  clay,  usually  mixed 
with  much  silt  and  some  sand. 

Silt  loams — Soils  with  more  than  50  percent  of  silt  and  less  than  15 
percent  of  clay,  mixed  with  some  sand. 

Loams — Soils  with  from  30  to  50  percent  of  sand  mixed  with  much 
silt  and  a little  clay. 

Sandy  loams — Soils  with  from  50  to  75  percent  of  sand. 

Fine  sandy  loams — Soils  with  from  50  to  75  percent  of  fine  sand  mixed 
with  much  silt  and  little  clay. 

Sands — Soils  with  more  than  75  percent  of  sand. 

Gravelly  loams — Soils  with  25  to  50  percent  gravel  with  much  sand  and 
some  silt. 

Gravels- — Soils  with  more  than  50  percent  of  gravel. 

Stony  loams — Soils  containing  a considerable  number  of  stones  over  one 
inch  in  diameter. 

Rock  outcrop — Usually  ledges  of  rock  having  no  agricultural  value. 

More  or  less  organic  matter  is  found  in  nearly  all  of  the  above  classes. 

Supply  and  Liberation  of  Plant  Food 

The  productive  capacity  of  land  in  humid  sections  depends  almost  wholly 
upon  the  power  of  the  soil  to  feed  the  crop;  and  this,  in  turn,  depends  both 
upon  the  stock  of  plant  food  contained  in  the  soil  and  upon  the  rate  at  which 
this  is  liberated,  or  rendered  soluble  and  available  for  use  in  plant  growth. 
Protection  from  weeds,  insects,  and  fungous  diseases,  tho  exceedingly  im- 
portant, is  not  a positive  but  a negative  factor  in  crop  production. 


30 


Soil  Report  No.  2 


[June, 


The  chemical  analysis  of  the  soil  gives  the  invoice  of  fertility  actually 
present  in  the  soil  strata  sampled  and  analyzed,  but  the  rate  of  liberation  is 
governed  by  many  factors,  some  of  which  may  be  controlled  by  the  farmer, 
while  others  are  largely  beyond  his  control.  Chief  among  the  important 
controllable  factors  which  influence  the  liberation  of  plant  food  are  lime- 
stone and  decaying  organic  matter,  which  may  be  added  to  the  soil  by  direct 
application  of  ground  limestone  and  farm  manure.  Organic  matter  may 
also  be  supplied  by  green-manure  crops  and  crop  residues,  such  as  clover, 
cowpeas,  straw,  and  cornstalks.  The  rate  of  decay  of  organic  matter  de- 
pends largely  upon  its  age  and  origin,  and  it  may  be  hastened  by  tillage.  The 
chemical  analysis  shows  correctly  the  total  organic  carbon,  which  repre- 
sents, as  a rule,  but  little  more  than  half  the  organic  matter:  so  that  20,000 
pounds  of  organic  carbon  in  the  plowed  soil  of  an  acre  corresponds  to 
nearly  20  tons  of  organic  matter.  But  this  organic  matter  consists  largely 
of  the  old  organic  residues  that  have  accumulated  during  the  past  centuries 
because  they  were  resistant  to  decay,  and  2 tons  of  clover  or  cowpeas 
plowed  under  may  have  greater  power  to  liberate  plant  food  than  the  20 
tons  of  old  inactive  organic  matter.  The  recent  history  of  the  individual 
farm  or  field  must  be  depended  upon  for  information  concerning  recent  ad- 
ditions of  active  organic  matter,  whether  in  applications  of  farm  manure, 
in  legume  crops,  or  in  grass-root  sods  of  old  pastures. 

Probably  no  agricultural  fact  is  more  generally  known  by  farmers  and 
landowners  than  that  soils  differ  in  productive  power.  Even  though  plowed 
alike  and  at  the  same  time,  prepared  the  same  way,  planted  the  same  day 
with  the  same  kind  of  seed,  and  cultivated  alike,  watered  by  the  same  rains 
and  warmed  by  the  same  sun,  nevertheless  the  best  acre  may  produce  twice 
as  large  a crop  as  the  poorest  acre  on  the  same  farm,  if  not,  indeed,  in  the 
same  field;  and  the  fact  should  be  repeated  and  emphasized  that  with  the 
normal  rainfall  of  Illinois  the  productive  power  of  the  land  depends  primarily 
upon  the  stock  of  plant  food  contained  in  the  soil  and  upon  the  rate  at  which 
it  is  liberated,  just  as  the  success  of  the  merchant  depends  primarily  upon  his 
stock  of  goods  and  the  rapidity  of  sales.  In  both  cases  the  stock  of  any 
commodity  must  be  increased  or  renewed  whenever  the  supply  of  such 
commodity  becomes  so  depleted  as  to  limit  the  success  of  the  business, 
whether  on  the  farm  or  in  the  store. 

As  the  organic  matter  decays,  certain  decomposition  products  are  formed, 
including  much  carbonic  acid,  some  nitric  acid,  and  various  organic  acids, 
and  these  have  power  to  act  upon  the  soil  and  dissolve  the  essential  mineral 
plant  foods,  thus  furnishing  nitrates,  phosphates,  and  other  salts  of  potas- 
sium, magnesium,  calcium,  etc.  for  the  use  of  the  growing  crop. 

As  already  explained  fresh  organic  matter  decomposes  much  more  rap- 
idly than  the  old  humus,  which  represents  the  organic  residues  most  resistant 
to  decay  and  which  consequently  have  accumulated  in  the  soil  during  the 
past  centuries.  The  decay  of  this  old  humus  can  be  hastened  both  by  tillage, 
which  maintains  a porous  condition  and  thus  permits  the  oxygen  of  the 
air  to  enter  the  soil  more  freely  and  to  effect  the  more  rapid  oxidation  of 
the  organic  matter,  and  also  by  incorporating  with  the  old  resistant  residues 
some  fresh  organic  matter,  such  as  farm  manure,  clover  roots,  etc.,  which 
decay  rapidly  and  which  thus  furnish  or  liberate  organic  matter  and  in- 
organic food  for  bacteria,  which,  under  such  favorable  conditions  appear  to 
have  power  to  attack  and  decompose  the  old  humus.  It  is  probably  for  this 
reason  that  peat,  a very  inactive  and  inefficient  fertilizer  when  used  by 


Moultrie  County 


JpT/] 


itself,  becomes  much  more  effective  when  incorporated  with  fresh  farm 
manure ; so  that,  when  used  together,  two  tons  of  the  mixture  may  be  worth 
as  much  as  two  tons  of  manure,  but  if  applied  separately,  the  peat  has 
little  value.  Bacterial  action  is  also  promoted  by  the  presence  of  limestone. 

It  should  be  kept  in  mind  that  crops  are  not  made  out  of  nothing.  They 
are  composed  of  ten  different  elements  of  plant  food,  every  one  of  which  is 
absolutely  essential  for  the  growth  and  formation  of  every  agricultural  plant. 
Of  these  ten  elements  of  plant  food,  only  two  (carbon  and  oxygen)  are  se- 
cured from  the  air  by  all  plants,  only  one  (hydrogen)  from  water,  and  seven 
from  the  soil.  Nitrogen,  one  of  these  seven  elements  secured  from  the  soil 
by  all  plants,  may  also  be  secured  from  the  air  by  one  class  of  plants  (le- 
gumes), in  case  the  amount  liberated  from  the  soil  is  insufficient;  but  even 
these  plants  (which  include  only  the  clovers,  peas,  beans,  and  vetches  among 
our  common  .agricultural  plants)  secure  only  from  the  soil  six  elements 
(phosphorus,  potassium,  magnesium,  calcium,  iron  and  sulfur),  and  also 
utilize  the  soil  nitrogen  so  far  as  it  becomes  soluble  and  available  during 
their  period  of  growth. 

Plants  are  made  of  these  plant-food  elements  in  just  the  same  sense  that 
a building  is  made  of  wood  and  iron,  brick,  stone,  and  mortar.  Without 
materials,  nothing  material  can  be  made.  The  normal  temperature,  sunshine, 
rainfall,  and  length  of  season  in  central  Illinois  are  sufficient  to  produce 
50  bushels  of  wheat  per  acre,  100  bushels  of  corn,  100  bushels  of  oats,  and 
4 tons  of  clover  hay;  and,  where  the  land  is  properly  drained  and  properly 
tilled,  such  crops  would  frequently  be  secured  if  the  plant  foods  were  pres- 
ent in  sufficient  amount  and  liberated  at  a sufficiently  rapid  rate  to  meet  the 
absolute  needs  of  the  crops. 


Crop  Requirements 

The  accofnpanying  table  shows  the  requirements  of  such  crops  for  the 
five  most  important  plant  food  elements  which  the  soil  must  furnish.  (Iron 
and  sulfur  are  supplied  normally  in  sufficient  abundance  compared  with  the 
amounts  needed  by  plants,  so  that  they  are  not  known  ever  to  limit  the  yield 
of  crops) : 


Table  A Plant  Food  in  Wheat,  Corn,  Oats,  and  Clover 


Produce 

Nitro- 

gen, 

pounds 

Phos- 

phorus, 

pounds 

Potas- 

sium, 

pounds' 

Magne- 

sium, 

pounds 

Cal- 

cium, 

pounds 

Kind 

Amount 

Wheat,  grain 

SO  bu. 

71 

12 

13 

4 

1 

Wheat  straw 

2 Yz  tons 

25 

4 

45 

4 

10 

Corn,  grain 

100  bu. 

100 

17 

19 

7 

1 

Corn  stover 

3 tons 

48 

6 

52 

10 

21 

Corn  cobs 

Yz  ton 

2 

2 

Oats,  grain 

100  bu. 

66 

11 

16 

2 

Oat  straw 

2 y2  tons 

31 

5 

52 

7 

15 

Clover  seed 

4 bu. 

7 

2 

3 

1 

1 

Clover  hay 

4 tons 

160 

20 

120 

31 

117 

Total  in  grain  and  seed 

244* 

42 

51 

16 

4 

Total  in  four  crops  . . . 

510* 

77 

322 

68 

168 

*These  amounts  include  the  nitrogen  contained  in  the  clover  seed  or  hay,  which, 
however,  may  be  secured  from  the  air. 


32 


Soil  Report  No.  2 


[June, 


To  be  sure,  these  are  large  yields,  but  shall  we  try  to  make  possible  the 
production  of  yields  only  half  or  a quarter  as  large  as  these,  or  shall  we 
set  as  our  ideal  this  higher  mark,  and  then  approach  it  as  nearly  as  pos- 
sible with  profit?  Among  the  four  crops,  corn  is  the  largest,  with  a total 
yield  of  more  than  six  tons  per  acre;  and  yet  the  100-bushel  crop  of  corn  is 
often  produced  on  rich  pieces  of  land  in  good  seasons.  In  very  practical 
and  profitable  systems  of  farming,  the  Illinois  Experiment  Station  has  pro- 
duced, as  an  average  of  the  six  years,  1905  to  1910,  a yield  of  87  bushels 
of  corn  per  acre  in  grain  farming  (with  limestone  and  phosphorus  applied, 
and  with  crop  residues  and  legume  crops  turned  under),  and  90  bushels  per 
acre  in  live-stock  farming  (with  limestone,  phosphorus,  and  manure). 

On  the  Fairfield  Experiment  Field  in  Wayne  County,  on  the  common 
prairie  land  of  southern  Illinois,  yields  have  been  obtained  as  high  as  90 
bushels  per  acre  of  corn,  and  3*4  tons  of  air-dry  clover  hay. 

The  importance  of  maintaining  a rich  surface  soil  cannot  be  too  strongly 
emphasized.  It  is  well  illustrated  by  data  from  the  Rothamsted  Experiment 
Station,  the  oldest  in  the  world.  Thus  on  Broadbalk  field,  where  wheat  has 
been  grown  since  1844,  the  average  yields  for  the  ten  years,  1892  to  1901 
were  12.3  bushels  per  acre  on  plot  3 (unfertilized)  and  31.8  bushels  on 
plot  7 (well  fertilized),  but  the  amounts  of  both  nitrogen  and  phosphorus 
in  the  subsoil  (9  to  27  inches)  were  distinctly  greater  in  plot  3 than  in 
plot  7,  thus  showing  that  the  higher  yields  from  plot  7 were  due  to  the 
fact  that  the  plowed  soil  had  been  enriched.  In  1893,  plot  7 contained  per 
acre  in  the  surface  soil  (o  to  9 inches)  about  600  pounds  more  nitrogen  and 
900  pounds  more  phosphorus  than  plot  3.  Even  a rich  subsoil  has  little 
value  if  it  lies  beneath  a worn-out  surface. 

Methods  op  Liberating  Plant  Food 

Limestone  and  decaying  organic  matter  are  the  principal  materials  the 
farmer  can  utilize  most  profitably  to  bring  about  the  liberation  of  plant  food. 

The  limestone  corrects  the  acidity  of  the  boil  and  thus  encourages  the 
development  not  only  of  the  nitrogen-gathering  bacteria  which  live  in  the 
nodules  on  the  roots  of  clover,  cowpeas,  and  other  legumes,  but  also  the 
nitrifying  bacteria  which  have  power  to  transform  the  insoluble  and  unavail- 
able organic  nitrogen  into  soluble  and  available  nitrate  nitrogen. 

At  the  same  time  the  products  of  this  decomposition  have  power  to  dis- 
solve the  minerals  contained  in  the  soil,  such  as  potassium  and  magnesium, 
and  also  to  dissolve  the  insoluble  phosphate  and  limestone  which  may  be 
applied  in  low-priced  forms. 

Tillage,  or  cultivation,  also  hastens  the  liberation  of  plant  food  by  per- 
mitting the  air  to  enter  the  soil  and  burn  out  the  organic  matter;  but  it 
should  never  be  forgotten  that  tillage  is  wholly  destructive,  that  it  adds 
nothing  whatever  to  the  soil,  but  always  leaves  the  soil  poorer.  Tillage 
should  be  practiced  so  far  as  is  necessary  to  prepare  a suitable  seed-bed  for 
root  development  and  also  for  the  purpose  of  killing  weeds,  but  more  than 
this  is  unnecessary  and  unprofitable  in  seasons  of  normal  rainfall;  and  it 
is  much  better  actually  to  enrich  the  soil  by  proper  applications  or  additions, 
including  limestone  and  organic  matter  (both  of  which  have  power  to  im- 
prove the  physical  condition  as  well  as  to  liberate  plant  food)  than  merely 
to  hasten  soil  depletion  by  means  of  excessive  cultivation. 


Moultrie  County 


33 


1911] 


Permanent  Soil  Improvement 

The  best  and  most  profitable  methods  for  the  permanent  improvement  of 
the  common  soils  of  Illinois  are  as  follows: 

(1)  If  the  soil  is  acid  apply  at  least  two  tons  per  acre  of  ground  lime- 
stone, preferably  at  times  magnesian  limestone  (CaC03  MgC03)  which 
contains  both  calcium  and  magnesium,  and  has  slightly  greater  power  to 
correct  soil  acidity,  ton  for  ton,  than  the  ordinary  calcium  limestone 
(CaC03)  ; and  continue  to  apply  about  two  tons  per  acre  of  ground  limestone 
every  four  to  six  years. 

(2)  Adopt  a good  rotation  of  crops,  including  a liberal  use  of  legumes, 
and  increase  the  organic  matter  of  the  soil  either  by  plowing  under  the 
legume  crops  and  other  crop  residues  (straw  and  corn  Stalks)  or  by  using 
for  feed  and  bedding  practically  all  of  the  crops  raised  and  returning  the 
manure  to  the  land  with  the  least  possible  loss.  No  one  can  say  in  advance 
what  will  prove  to  be  the  best  rotation  of  crops,  because  of  variation  in 
farms  and  farmers,  and  in  prices  for  produce,  but  the  following  are  sug- 
gested to  serve  as  models  or  outlines : 

First  year,  corn  (with  some  winter  legume,  such  as  red  clover,  alsike,  sweet  clover, 
or  alfalfa,  or  a mixture,  seeded  on  part  of  the  field  at  the  last  cultivation). 

Second  year,  oats  or  barley  or  wheat  (fall  or  spring)  on  one  part  and  cowpeas  or 
soybeans  where  the  winter  catch  crop  is  plowed  down  late  in  the  spring. 

Third  year,  wheat  or  oats  (with  clover  or  clover  and  grass). 

Fourth  year,  clover  or  clover  and  grass. 

Fifth  year,  wheat  and  clover  or  grass  and  clover. 

Sixth  year,  clover  or  clover  and  grass. 


Of  course  there  should  be  as  many  fields  as  there  are  years  in  the  ro- 
tation. In  grain  farming,  with  wheat  grown  the  third  and  fifth  years,  most 
of  the  coarse  products  should  be  returned  to  the  soil,  and  the  clover  may  be 
clipped  and  left  on  the  land  (only  the  clover  seed  being  sold  the  fourth  and 
sixth  years)  ; or,  in  live-stock  farming,  the  field  may  be  used  three  years 
for  timothy  and  clover  pasture  and  meadow  if  desired.  The  system  may  be 
reduced  to  a five-year  rotation  by  cutting  out  either  the  second  or  the 
sixth  year;  and  to  a four-year  system  by  omitting  the  fifth  and  sixth 
years. 

With  two  years  of  corn,  followed  by  oats  with  clover-seeding  the  third 
year,  and  by  clover  the  fourth  year,  all  produce  can  be  used  for  feed  and 
bedding  if  other  land  is  available  for  permanent  pasture.  Alfalfa  may  be 
grown  on  a fifth  field  for  four  or  eight  years,  which  is  to  be  alternated  with 
one  of  the  four;  or  the  alfalfa  may  be  moved  every  five  years,  and  thus 
rotated  over  all  five  fields  every  twenty-five  years. 

Other  four-year  rotations  more  suitable  for  grain  farming  are: 

Wheat  (and  clover),  corn,  oats,  and  clover;  or  corn  (and  clover),  cow-peas,  wheat 
and  clover.  (Alfalfa  may  be  grown  on  a fifth  field  and  rotated  every  five 
years,  the  hay  being  sold.) 

Good  three-year  rotations  are : 

Corn,  oats,  and  clover;  corn,  wheat,  and  clover;  or  wheat  (and  clover),  corn  (and 
clover),  and  cow-peas,  in  which  two  catch  crops  and  one  regular  crop  of  legumes 
are  grown  in  three  years. 


34 


Soil  Report  No.  2 


[June, 


A five-year  rotation  of  corn  (and  clover),  cow-peas,  wheat,  clover, 
wheat  (and  clover)  allows  legumes  to  be  seeded  four  times,  and  alfalfa 
may  be  grown  on  a sixth  field  for  five  or  six  years  in  the  combination 
rotation,  alternating  between  two  fields  every  five  years,  or  rotating  over 
all  fields  if  moved  every  six  years. 

I o avoid  clover  sickness  it  may  sometimes  be  necessary  to  substitute 
red  clover  or  alsike  for  the  other  in  about  every  third  rotation,  and  at  the 
same  time  to  discontinue  their  use  in  the  catch-crop  mixture.  If  the  corn 
crop  is  not  too  rank,  cowpeas  or  soybeans  may  also  be  used  as  a catch-crop 
(seeded  at  the  last  cultivation)  in  the  southern  part  of  the  state  and,  if 
necessary  to  avoid  disease,  these  may  well  alternate  in  successive  rotations. 

For  easy  figuring  it  may  well  be  kept  in  mind  that  the  following  amounts 
of  nitrogen  are  required  for  the  produce  named : 

1 bushel  of  oats  (grain  and  straw)  requires  1 pound  of  nitrogen. 

1 bushel  of  corn  (grain  and  stalks)  requires  il/2  pounds  of  nitrogen. 

1 bushel  of  wheat  (grain  and  straw)  requires  2 pounds  of  nitrogen. 

1 ton  of  timothy  requires  24  pounds  of  nitrogen. 

1 ton  of  clover  contains  40  pounds  of  nitrogen. 

1 ton  of  cowpeas  contains  43  pounds  of  nitrogen. 

1 ton  of  average  manure  contains  10  pounds  of  nitrogen. 

The  roots  of  clover  contain  about  half  as  much  nitrogen  as  the  tops, 
and  the  roots  of  cowpeas  contain  about  one-tenth  as  much  as  the  tops. 

Soils  of  moderate  productive  power  will  furnish  as  much  nitrogen  to 
clover  (and  two  or  three  times  as  much  to  cowpeas)  as  will  be  left  in  the 
roots  and  stubble.  For  grain  crops,  as  wheat,  corn,  and  oats,  about  two- 
thirds  of  the  nitrogen  is  contained  in  the  grain  and  one-third  in  the  straw 
or  stalks. 

(3)  On  all  lands  deficient  in  phosphorus  (except  on  those  susceptible 
to  serious  erosion  by  surface  washing  or  gullying)  apply  that  element  in 
considerably  larger  amounts  than  are  required  to  meet  the  actual  needs  of 
the  crops  desired  to  be  produced.  The  abundant  information  thus  far  se- 
cured shows  positively  that  fine-ground  natural  rock  phosphate  can  be  used 
successfully  and  very  profitably,  and  clearly  indicates  that  this  material 
will  be  the  most  economical  form  of  phosphorus  to  use  in  all  ordinary  sys- 
tems of  permanent,  profitable  soil  improvement.  The  first  application  may 
well  be  one  ton  per  acre,  and  subsequently  about  one-half  ton  per  acre 
every  four  to  six  years  should  be  applied,  at  least  until  the  phosphorus 
content  of  the  plowed  soil  reaches  2,000  pounds  per  acre,  which  may  require 
a total  application  of  from  three  to  five  or  six  tons  per  acre  of  raw  phos- 
phate containing  12)^  percent  of  the  element  phosphorus. 

Steamed  bone  meal  and  even  acid  phosphate  may  be  used  in  emergencies, 
but  it  should  always  be  kept  in  mind  that  phosphorus  delivered  in  Illinois 
costs  about  3 cents  a pound  in  raw  phosphate  (direct  from  the  mine  in  car- 
load lots),  but  10  cents  a pound  in  steamed  bone  meal,  and  about  12  cents 
a pound  in  acid  phosphate,  both  of  which  cost  too  much  per  ton  to  permit 
their  common  purchase  by  farmers  in  carload  lots,  which  is  not  the  case 
with  limestone  or  raw  phosphate. 

Phosphorus  once  applied  to  the  soil  remains  in  it  until  removed  in 
crops,  unless  carried  away  mechanically  by  soil  erosion.  (The  loss  by 
leaching  is  only  about  ip2  pounds  per  acre  per  annum,  so  that  more  than 
150  years  would  be  required  to  leach  away  the  phosphorus  applied  in  one 
ton  of  raw  phosphate.) 


Moultrie  County 


35 


19a] 


The  phosphate  and  limestone  may  be  applied  at  any  time  during  the 
rotation,  but  a good  method  is  to  apply  the  limestone  after  plowing  and 
work  it  into  the  surface  soil  in  preparing  the  seed  bed  for  wheat,  oats,  rye, 
or  barley,  where  clover  is  to  be  seeded ; while  phosphate  is  best  plowed  under 
with  farm  manure,  clover,  or  other  green  manures,  which  serve  to  liberate 
the  phosphorus. 

(4)  Until  the  supply  of  decaying  organic  matter  has  been  made  ade- 
quate, on  the  poorer  types  of  upland  timber  and  gray  prairie  soils  some 
temporary  benefit  may  be  derived  from  the  use  of  a soluble  salt  or  mixture 
of  salts,  such  as  kainit,  which  contains  both  potassium  and  magnesium  in 
soluble  form  and  also  some  common  salt  (sodium  chlorid).  About  600 
pounds  per  acre  of  kainit  applied  and  turned  under  with  the  raw  phosphate 
will  help  to  dissolve  the  phosphorus  as  well  as  to  furnish  available  potas- 
sium and  magnesium,  and  for  a few  years  such  use  of  kainit  will  no 
doubt  be  profitable  on  lands  deficient  in  organic  matter,  but  the  evidence  thus 
far  secured  indicates  that  its  use  is  not  absolutely  necessary  and  that  it  will 
not  be  profitable  after  adequate  provision  is  made  for  decaying  organic  mat- 
ter, since  this  will  necessitate  returning  to  the  soil  either  all  produce  except 
the  grain  (in  grain  farming)  or  the  manure  produced  in  live-stock  farm- 
ing. (Where  hay  or  straw  are  sold,  manure  should  be  bought.) 

On  soils  which  are  subject  to  surface  washing,  including  especially  the 
yellow  silt  loam  of  the  upland  timber  area,  and  to  some  extent  the  yellow- 
gray  silt  loam,  and  other  more  rolling  areas,  the  supply  of  minerals  in  the 
subsurface  and  subsoil  (which  gradually  renew  the  surface  soil)  tend  to 
provide  for  a low-grade  system  of  permanent  agriculture  if  some  use  is  made 
of  legume  plants,  as  in  long  rotations  with  much  pasture,  because  both  the 
minerals  and  nitrogen  are  thus  provided  in  some  amount  almost  permanently ; 
but  where  such  lands  are  farmed  under  such  a system  not  more  than  two  or 
three  grain  crops  should  be  grown  during  a period  of  ten  or  twelve  years, 
the  land  being  kept  in  pasture  most  of  the  time ; and  where  the  soil  is  acid  a 
liberal  use  of  limestone,  as  top  dressings  if  necessary,  and  occasional  re- 
seeding with  clovers  will  benefit  both  the  pasture  and  indirectly  the  grain 
crops. 


Advantage  oe  Crop  Rotation  and  Permanent  Systems 

It  should  be  noted  that  clover  is  not  likely  to  be  well  infected  with  the 
clover  bacteria  during  the  first  rotation  on  a given  farm  or  field  where  it 
has  not  been  grown  before  within  recent  years;  but  even  a partial  stand  of 
clover  the  first  time  will  probably  provide  a thousand  times  as  many  bac- 
teria for  the  next  clover  crop  as  ong  could  afford  to  apply  in  artificial  inocu- 
lation, for  a single  root-tubercle  Thay;  contain  a million  bacteria  developed 
from  one  during  the  season’s  growth’. 

This  is  only  one  of  several  advantages  of  the  second  course  of  the  rota- 
tion over  the  first  course.  Thus  the  there  practice  of  crop  rotation  is  an  ad- 
vantage, especially  in  helping  to  rid  'tKe  land  of  insects  and  foul  grass  and 
weeds.  The  deep-rooting  clover  crop  is’  an  advantage  to  subsequent  crops 
because  of  that  characteristic.  The  larger  applications  of  organic  manures 
(made  possible  by  the  larger  crops)  are  a great  advantage;  and  in  systems 
of  permanent  soil  improvement,  such  as  are  here  advised  and  illustrated, 
more  limestone  and  more  phosphorus  are  provided  than  are  needed  for  the 
meager  or  moderate  crops  produced  during  the  first  rotation,  and  conse- 
quently the  crops  in  the  second  rotation  have  the  advantage  of  such  accumu- 


36 


Soil  Report  No.  2 


[June, 


latecl  residues  (well  incorporated  with  the  plowed  soil)  in  addition  to  the 
regular  applications  made  during  the  second  rotation. 

This  means  that  these  systems  tend  positively  toward  the  making  of 
richer  land.  The  ultimate  analyses  recorded  in  the  Tables  give  the  absolute 
invoice  of  these  Illinois  soils.  They  show  that  most  of  them  are  positively 
deficient  only  in  limestone,  phosphorus,  and  nitrogenous  organic  matter ; and 
the  accumulated  information  from  careful  and  long-continued  investiga- 
tions in  different  parts  of  the  United  States  clearly  establish  the  fact  that 
in  general  farming  these  essentials  can  be  supplied  with  greatest  economy 
and  profit  by  the  use  of  ground  natural  limestone,  very  finely  ground  natural 
rock  phosphate,  and  legume  crops  to  be  plowed  under  directly  or  in  farm 
manure.  On  normal  soils  no  other  applications  are  absolutely  necessary, 
but,  as  already  explained,  the  addition  of  some  soluble  salt  in  the  beginning 
of  a system  of  improvement  on  some  of  these  soils  produces  temporary 
benefit,  and  if  some  inexpensive  salt  such  as  kainit  is  used  it  may  produce 
sufficient  increase  to  more  than  pay  the  added  cost. 

The  Potassium  Problem 

As  reported  in  Illinois  Bulletin  123,  where  wheat  has  been  grown  every 
year  for  more  than  half  a century  at  Rothamsted,  England,  exactly  the  same 
increase  was  produced  (5.6  bushels  per  acre),  as  an  average  of  the  first 
24  years,  whether  potassium,  magnesium,  or  sodium  was  applied,  the  rate  of 
application  per  annum  being  200  pounds  of  potassium  sulfate  and  molecular 
equivalents  of  magnesium  sulfate  and  sodium  sulfate.  As  an  average  of 
59  years  (1852  to  1910)  the  yield  of  wheat  has  been  12.7  bushels  on  un- 
treated land,  23.3  bushels  where  86  pounds  of  nitrogen  and  29  pounds  of 
phosphorus  per  acre  per  annum  were  applied;  and,  as  further  additions,  85 
pounds  of  potassium  raised  the  yield  to  31.3  bushels;  52  pounds  of  mag- 
nesium raised  it  to  29.3  bushels;  and  50  pounds  of  sodium  raised  it  to 
29.5  bushels.  Where  potassium  was  applied  the  average  wheat  crop  re- 
moved 40  pounds  of  that  element  in  the  grain  and  straw,  or  three  times  as 
much  as  would  be  removed  in  the  grain  only  for  such  crops  as  are  suggested 
in  Table  A.  The  Rothamsted  soil  contained  abundance  of  limestone,  but  no 
organic  matter  was  provided  except  the  little  in  the  stubble  and  roots  of  the 
wheat  plants. 

On  another  field  at  Rothamsted  the  average  yield  of  barley  for  59  years 
(1852  to  1910)  has  been  14.4  bushels  on  untreated  land,  38.6  bushels  where 
43  pounds  of  nitrogen  and  29  pounds  of  phosphorus  have  been  applied 
per  acre  per  annum;  while  the  further  addition  of  85  pounds  of  potassium, 
19  pounds  of  magnesium,  and  14  pounds  of  sodium  (all  in  sulfates)  raised 
the  average  yield  to  41.7  bushels,  but,  where  only  70  pounds  of  sodium  were 
applied  in  addition  to  the  nitrogen  and  phosphorus,  the  average  has  been 
43.3  bushels.  Thus,  as  an  average  of  59  years,  the  use  of  sodium  pro- 
duced 1.8  bushels  less  wheat  and  1.6  bushels  more  barley  than  the  use  of 
potassium,  with  both  grain  and  straw  removed  and  no  organic  manures 
returned. 

In  recent  years  the  effect  of  potassium  is  becoming  much  more  marked 
than  that  of  sodium  or  magnesium,  on  the  wheat  crop;  but  this  must  be 
expected  to  occur  in  time  where  no  potassium  is  returned  in  straw  or 
manure,  and  no  provision  made  for  liberating  potassium  from  the  supply 
still  remaining  in  the  soil.  If  more  than  three-fourths  of  the  potassium 
removed  were  returned  in  the  straw  (see  Table  A),  and  if  the  decomposi- 


jp/j] 


Moultrie  County 


37 


tion  products  of  the  straw  have  power  to  liberate  additional  amounts  of  po- 
tassium from  the  soil,  the  necessity  of  purchasing  potassium  in  a good 
system  of  farming  on  such  land  is  very  remote. 

While  about  half  of  the  potassium,  nitrogen,  and  organic  matter,  and 
about  one-fourth  of  the  phosphorus,  contained  in  manure,  will  be  lost  by 
three  or  four  months’  exposure  in  the  ordinary  pile  in  the  barn  yard,  there 
.is  practically  no  loss  if  plenty  of  absorbent  bedding  is  used  on  cement  floors, 
and  if  the  manure  is  hauled  to  the  field  and  spread  within  a day  or  two 
after  it  is  produced.  Again,  while  the  animals  destroy  two-thirds  of  the 
■organic  matter  and  retain  one-fourth  of  the  nitrogen  and  phosphorus  in 
-average  live-stock  farming,  they  retain  less  than  one-tenth  of  the  potassium, 
from  the  food  consumed;  so  that  the  actual  loss  of  potassium  in  the  products 
sold  from  the  farm,  either  in  grain  farming  or  in  live-stock  farming,  is 
wholly  negligible  on  land  containing  25,000  pounds  or  more  of  potassium 
in  the  surface  6^  inches. 

The  removal  of  one  inch  of  soil  per  century  by  surface  washing  (which 
is  likely  to  occur  wherever  there  is  satisfactory  surface  drainage  and  frequent 
■cultivation)  would  permanently  maintain  the  potassium  in  grain  farming 
by  renewal  from  the  subsoil,  provided  one-third  of  the  potassium  is  removed 
■by  cropping  before  the  soil  is  carried  away. 

From  all  of  these  facts  it  will  be  seen  that  the  potassium  problem  is 
not  one  of  supply  but  of  liberation;  and  the  Rothamsted  records  show  that 
for  many  years  other  soluble  salts  have  practically  the  same  power  as  po- 
tassium to  increase  crop  yields  in  the  absence  of  sufficient  decaying  organic 
matter.  Whether  this  action  relates  to  supplying  or  liberating  potassium  for 
its  own  sake,  or  to  the  power  of  the  soluble  salt  to  increase  the  availability 
■of  phosphorus  or  other  elements,  it  is  not  known,  but  where  much  potassium 
is  removed,  as  in  the  entire  crops  at  Rothamsted  with  no  return  of  organic 
residues,  probably  the  soluble  salt  functions  in  both  ways. 

As  an  average  of  112  separate  tests  conducted  in  1907,  1908,  1909  and 
1910,  on  the  Fairfield  Experiment  Field,  an  application  of  200  pounds  of 
potassium  sulfate,  containing  85  pounds  of  potassium  costing  $5.10,  in- 
creased the  yield  of  corn  by  9.3  bushels  per  acre;  while  600  pounds  of  kainit, 
containing  only  60  pounds  of  potassium  and  costing  $4.00,  gave  an  increase 
of  10.7  bushels.  Thus,  at  40  cents  a bushel  for  corn,  the  kainit  has  paid  for 
itself ; but  these  results,  like  those  at  Rothamsted,  were  secured  where  no 
adequate  provision  had  been  made  for  decaying  organic  matter. 

Additional  experiments  at  Fairfield  include  an  equally  complete  test  with 
potassium  sulfate  and  kainit  on  land  to  which  8 tons  per  acre  of  farm 
manure  had  been  applied.  As  an  average  of  112  tests  with  each  material, 
the  200  pounds  of  potassium  sulfate  increased  the  yield  of  corn  by  1.7  bush- 
els, while  the  600  pounds  of  kainit  also  gave  an  increase  of  1.7  bushels. 
Thus,  where  organic  manure  was  supplied,  very  little  effect  was  pro- 
duced by  the  addition  of  either  potassium  sulfate  or  kainit;  in  part  perhaps 
because  the  potassium  removed  in  the  crops  is  mostly  returned  in  the  manure 
if  properly  cared  for:  and  perhaps  in  larger  part  because  the  decaying 
organic  matter  helps  to  liberate  and  hold  in  solution  other  plant  food  ele- 
ments, especially  phosphorus. 

In  laboratory  experiments  at  the  Illinois  Experiment  Station,  it  has 
been  shown  that  potassium  salts  and  most  other  soluble  salts  increase  the 
solubility  of  the  phosphorus  in  soil  and  in  rock  phosphate  as  determined  bv 
chemical  analysis;  also  that  the  addition  of  glucose  with  rock  phosphate  in 


38 


Soil  Report  No.  2 


pot-culture  experiments  increases  the  availability  of  the  phosphorus,  as  meas- 
ured by  plant  growth,  altho  the  glucose  consists  only  of  carbon,  hydrogen, 
and  oxygen,  add  thus  contains  no  plant  food  of  value. 

If  we  remember  that,  as  an  average,  live  stock  destroy  two-thirds  of 
the  organic  matter  of  the  food  consumed,  it  is  easy  to  determine  from 
Table  A that  more  organic  matter  will  be  supplied  in  a proper  grain  sys- 
tem than  in  a strictly  live-stock  system;  and  the  evidence  thus  far  secured 
from  older  experiments  at  the  University  and  at  other  places  in  the  state 
indicates  that  if  the  corn  stalks,  straw,  clover,  etc.,  are  incorporated  with 
the  soil  as  soon  as  practicable  after  they  are  produced  (which  can  usually 
be  done  in  the  late  fall  or  early  spring),  there  is  little  or  no  difficulty  in 
securing  sufficient  decomposition  in  our  humid  climate  to  avoid  serious  in- 
terference with  the  capillary  movement  of  - the  soil  moisture,  a common 
danger  from  plowing  under  too  much  coarse  manure  of  any  kind  in  the 
late  spring  of  a dry  year. 

If,  however,  the  entire  produce  of  the  land  is  sold  from  the  farm,  as 
in  hay  farming,  or  when  both  grain  and  straw  are  sold,  of  course  the  draft 
on  potassium  will  then  be  so  great  that  in  time  it  must  be  renewed  by  some 
sort  of  application.  As  a rule,  such  farmers  ought  to  secure  manure  front 
town,  since  they  furnish  the  bulk  of  the  material  out  of  which  the  manure 
is  produced. 

Calcium  and  Magnesium 

When  measured  by  the  actual  crop  requirements  for  plant  food,  mag- 
nesium and  calcium  are  more  limited  in  some  Illinois  soils  than  potassium. 
But  with  these  elements  we  must  also  consider  the  loss  by  leaching.  As  an 
average  of  90  analyses*  of  Illinois  well-waters  drawn  chiefly  from  glacial 
sands,  gravels,  or  till,  3 million  pounds  of  water  (about  the  average  annual 
drainage  per  acre  for  Illinois)  contained  11  pounds  of  potassium,  130  of  mag- 
nesium, and  330  of  caldium.  These  figures  are  very  significant,  and  it  may 
be  stated  that  if  the  plowed  soil  is  well  supplied  with  the  carbonates  of  mag- 
nesium and  calcium,  then  a very  considerable  proportion  of  these  amounts 
will  be  leached  from  that  stratum.  Thus  the  loss  of  calcium  from  the  plowed 
soil  of  an  acre  at  Rothamsted,  England,  where  the  soil  contains  plenty  of 
limestone,  has  averaged  more  than  300  pounds  a year  as  determined  by 
analyzing  the  soil  in  1865  and  again  in  1905.  And  practically  the  same 
amount  of  calcium  was  found  by  analyzing  the  Rothamsted  drainage  waters. 

It  is  of  interest  to  note  that  thirty  crops  of  clover  of  four  tons  each 
would  require  3,510  pounds  of  calcium,  while  the  most  common  prairie 
land  of  southern  Illinois  contains  only  3,420  pounds  of  total  calcium  in  the 
plowed  soil  of  an  acre.  (See  Soil  Report  No.  1.)  Thus  limestone  has  a posi- 
tive value  on  some  soils  for  the  plant  food  which  it  supplies,  in  addi- 
tion to  its  value  in  correcting  soil  acidity  and  in  improving  the  physical 
condition  of  the  soil.  Ordinary  limestone  (abundant  in  the  southern  and 
western  parts  of  the  State)  contains  nearly  800  pounds  of  calcium  per  ton; 
while  a good  grade  of  clolomitic  limestone  (the  more  common  limestone  of 
northern  Illinois)  contains  about  400  pounds  of  calcium  and  300  pounds 
of  magnesium  per  ton.  Both  of  these  elements  are  furnished  in  readily 
available  form  in  ground  dolomitic  limestone. 


*Reported  by  Doctor  Bartow  and  associates,  of  the  Illinois  State  Water  Survey. 


UNIVERSITY  OF  ILLINOIS 

Agricultural  Experiment  Station 

SOIL  REPORT  NO.  3 

HARDIN  COUNTY  SOILS 


By  CYRIL,  G.  HOPKINS,  J.  G.  MOSIER, 
J.  H.  PETTIT  and  J.  E.  READHIMER 


URBANA,  ILLINOIS,  AUGUST,  1912 


State  Advisory  Committee  on  Soil  Investigations 
Ralph  Allen,  Delavan 
F.  I.  Mann,  Gilman 
A.  N.  Abbott,  Morrison 
J.  P.  Mason,  Elgin 
C.  V.  Gregory,  Chicago 

Agricultural  Experiment  Station  Staff  on  Soil  Investigations 
Eugene  Davenport,  Director 

Cyril  G.  Hopkins,  Chief  in  Agronomy  and  Chemistry 
Soil  Survey — 

J.  G.  Mosier,  Chief 
A.  F.  Gustafson,  Associate 
S.  V.  Holt,  Assistant 
H.  W.  Stewart,  Assistant 
H.  C.  Wheeler,  Assistant 
F.  A.  Fisher,  Assistant 
P.  E.  Karraker,  Assistant 
F.  M.  W.  Wascher,  Assistant 

Soil  Analysis — 

J.  H.  Pettit,  Chief 
E.  Van  Alstine,  Associate 
J.  P.  Aumer,  Assistant 
Gertrude  Niederman,  Assistant 
W.  H.  Sachs,  Assistant 
W.  R.  Leighty,  Assistant 
J.  T.  Flohil,  Assistant 

Soil  Experiment  Fields — 

J.  E.  Readhimer,  Superintendent 
Wm.  G.  Eckhardt,*  Associate 
O.  S.  Fisher,  Assistant 
J.  E.  Whitchurch,  Assistant 

E.  E.  Hoskins,  Assistant 

F.  W.  Garrett,  Assistant 
F.  C.  Bauer,  Assistant 

Soils  Extension — 

C.  C.  Logan,  Associate 


fOn  leave. 


HARDIN  COUNTY  SOILS 

By  CYRIE  G.  HOPKINS,  J.  G.  MOSIER,  J.  H.  PETTIT  and  J.  E.  READH1MER 


Introduction 

The  counties  of  Hardin,  Pope,  Johnson,  Union,  Alexander,  Pulaski  and 
Massac  include  most  of  the  unglaciated  area  of  southern  Illinois.  The  Ozark 
Hills  extend  across  this  area  from  west  to  east,  and  in  places  project  into 
the  next  tier  of  counties  on  the  north.  The  hill  lands  represent  the  most 
extensive  soil  types  in  these  seven  counties,  altho  the  bottom  lands  are  also 
very  important,  and  quite  extensive  in  the  southern  portion,  including  the 
Mississippi,  Ohio,  Cash  and  Big  Bay  bottoms. 

Hardin  county  is  representative  of  the  unglaciated  area  in  southern  Illi- 
nois, but  the  information  contained  in  this  report  on  “Hardin  County  Soils” 
is  applicable  not  only  to  the  other  counties  in  this  area,  but  also  to  the  hill 
lands  in  the  lower  Illinoisan  glaciation  lying  between  the  Ozark  Hills  and  the 
corn  belt;  and  even  in  the  corn-belt  counties  there  are  some  hill  lands, 
especially  near  the  larger  streams,  whose  chief  difference  from  the  Ozark 
Hills  is  the  lower  degree  of  acidity  in  the  northern  soils. 

For  information  concerning  the  soils  of  the  prairie  counties  of  the  wheat 
belt  of  Illinois,  the  reader  is  referred  to  Soil  Report  No.  I,  “Clay  County 
Soils”;  and  for  information  concerning  most  of  the  important  soil  types  of 
the  corn  belt,  he  is  referred  to  Soil  Report  No.  2,  “Moultrie  County  Soils.” 
In  addition  it  may  be  stated  that  Bulletin  123,  “The  Fertility  in  Illinois 
Soils,”  shows  the  great  soil  areas  of  the  state  and  gives  the  composition  of 
the  most  important  soil  types  in  each  area  and  much  information  relating  to 
their  improvement. 

Soil  Formation 

Hardin  county  is  situated  in  the  southeastern  part  of  the  state  on  the 
Ohio  river,  entirely  within  the  unglaciated  area.  The  altitude  above  sea  level 
varies  from  slightly  over  300  feet  to  more  than  800  feet,  thus  giving  a relief 
of  500  feet  in  the  county,  the  topography  over  almost  the  entire  county 
being  characterized  by  hills  and  valleys.  As  a result  of  the  topography  and 
of  the  somewhat  heavy  rainfall,  water  has  been  and  is  now  a very  active 
agent  in  soil  formation  or  modification. 

The  chief  material  composing  the  soils  of  Hardin  county  is  a wind-blown 
dust  known  as  loess.  Altho  the  county  has  never  been  glaciated  it  has  no 
purely  residual  soil  formed  by  the  disintegration  and  partial  decomposition 


2 


Soil  Report  No.  3 


[August, 


of  rocks  in  place,  the  residual  material  having  been  buried  beneath  the  de- 
posit of  loess  to  a depth  of  5 to  20  feet,  altho  on  some  of  the  stony  slopes 
the  soil  is  a mixture  of  residual  and  wind-blown  material,  and  might  prop- 
erly be  called  residuo-loessial  or  residuo-aeolial  soil. 

The  following  table  gives  the  soil  types,  the  areas  in  acres  and  square 
miles,  and  the  percentage  of  each  type  of  total  area  in  the  county. 


Table  1. — Soil  Types  of  Hardin  County 


Soil 

type 

No. 

Names 

Area  in 
square 
miles 

Area  in 
acres 

Percent 

of 

total 

135 

(a)  Upland  Timber  Soils  (page  13) 

Yellow  silt  loam 

120.15 

76,896.0 

70.56 

134 

Yellow-gray  silt  loam 

10.50 

6,720.0 

6.17 

864 

Yellow  fine  sandy  loam 

.46 

294.4 

.27 

198 

Stony  loam 

17.05 

10,912.0 

10.01 

199 

Rock  outcrop  

3.58 

2,291.2 

2.10 

1323 

(b)  Swamp  and  Bottom-land  Soils  (page  18)- 
Red-brown  clay  loam 

3.16 

2,022.4 

1.86 

1331 

Deep  gray  silt  loam 

1.20 

768.0 

.66 

1361.1 

Mixed  fine  sandy  loam : 

12.61 

8,070.4 

7.40 

1380 

River  sand 

.20 

130.5 

.12 

1516 

(c)  Terrace  Soils  (page  20) 

Gray  clay 

.31 

195.8 

.17 

1530 

Gray  silt  loam  on  tight  clay. 

1.18 

755.2 

.68 

Totals 

170.40 

109,055.9 

100.00 

THE  INVOICE  AND  INCREASE  OF  FERTILITY  IN  HARDIN 
COUNTY  SOILS 

Soil  Analysis 

To  appreciate  the  value  of  the  essential  elements  of  fertility  for  crops, 
we  should  keep  in  mind  that  food  for  plants  is  just  as  important  as  food  for 
animals.  In  the  Appendix  will  be  found  a more  comprehensive  discussion 
of  this  general  subject,  which  should  be  read  and  studied  in  advance  by  those 
who  are  not  familiar  with  the  fundamental  principles  involved;  and  in  any 
case  the  reader  should  carry  in  mind  the  plant  food  requirements  for  crops 
and  the  loss  of  plant  food  from  soils  by  leaching.  (See  Table  A and  the 
closing  pages  of  the  Appendix.) 

In  brief,  all  agricultural  plants  are  composed  of  ten  elements  of  plant 
food,  of  which  two  (carbon  and  oxygen)  are  secured  from  the  air,  one 
(hydrogen)  from  water,  and  seven  (nitrogen,  phosphorus,  potassium,  mag- 
nesium, calcium,  iron,  and  sulfur)  are  taken  from  the  soil.  Legume  crops, 
such  as  the  clovers,  peas,  and  beans,  may,  under  suitable  conditions,  secure 
more  or  less  of  their  nitrogen  from  the  air  in  case  the  amount  furnished  by 
the  soil  is  insufficient.  The  supply  of  iron  in  soils  is  so  great  that  it  need  not 
be  further  considered,  and  so  far  as  we  know  the  supply  of  sulfur  in  the 
soil,  supplemented  by  the  sulfur  brought  to  the  soil  in  rain  and  otherwise, 
is  sufficient  to  meet  all  requirements  of  common  farm  crops  for  that  ele- 
ment. 

We  need  to  give  special  consideration  to  the  five  elements  nitrogen,  phos- 
phorus, potassium,  magnesium,  and  calcium,  and  in  addition  we  should  not 
only  provide  against  soil  acidity,  but  insure  the  presence  of  limestone. 


POPE  COUNTY 


R.  7 E 

SALINE  ). 


? HARDIN  COUNTY 
UNIVERSITY  OF  ILLINOIS  AGRICULTURAL  EXPERIMENT  STATION 


terrace  soils 


Reddish  brown  clay  loam 


UPLAND  TIMBER  SOILS 
Yellow-gray  silt  loarr 


ne  sandy  loam 


Yellow  fir 


Hardin  County 


3 


1912] 


In  Table  1 are  recorded  the  average  amounts  of  these  important  elements 
per  acre  to  a depth  of  6%  inches  for  all  of  the  different  types  of  soil  in 
Hardin  county.  The  table  also  shows  the  amount  of  limestone,  if  present, 
or  the  amount  of  limestone  required  to  neutralize  or  destroy  the  acidity  pres- 
ent. The  organic  carbon  is  the  best  measure  of  the  organic  matter  (par- 
tially decayed  vegetable  matter)  ; and,  as  explained  in  the  Appendix,  the 
ratio  of  carbon  to  nitrogen  gives  some  indication  of  the  age  or  condition  of 
the  organic  matter.  Approximately  one-half  of  the  organic  matter  of  the 
soil  is  carbon,  so  that  12,880  pounds  of  carbon,  for  example,  correspond  to 
about  12  tons  per  acre  of  organic  matter. 

Two  million  pounds  per  acre  (about  62/t,  inches  deep)  represents  at 
least  as  much  soil  as  is  ordinarily  turned  in  plowing.  This  is  the  soil  with 
which  we  finally  incorporate  the  farm  manure,  phosphate,  limestone,  or 
other  fertilizer  applied  to  the  soil ; and  this  is  the  soil  stratum  upon  which 
we  must  depend  in  large  part  to  furnish  the  necessary  plant  food  for  the 
production  of  the  common  crops,  as  will  be  better  understood  from  the  in- 
formation given  in  the  Appendix.  As  there  stated,  even  a rich  subsoil  has 
but  little  value  if  it  lies  beneath  a worn-out  surface.  If,  however,  the  surface 
soil  is  enriched,  the  strong,  vigorous  plants  will  have  power  to  secure  more 
plant  food  from  the  subsurface  and  subsoil  than  would  be  the  case  with  weak, 
shallow-rooted  plants. 


Table  2. — Fertility  in  the  Soils  of  Hardin  County,  Illinois 
Average  pounds  per  acre  in  2 million  pounds  of  surface  soil  (about  0 to  6%  inches) 


Soil 

type 

No. 

Soil  type 

Total 

organic 

carbon 

Total 

nitro- 

gen 

Total 

phos- 

phorus 

Total 

potas- 

sium 

Total 

magne- 

sium 

Total 

calci- 

um 

Lime- 

stone 

present 

Lime- 

stone 

required 

Upland  Timber  Soils 

135 

Yellow  silt  loam 

12880 

1250 

840 

I 34200 

7710 

3980 

2100 

134 

Yellow-gray  silt 

loam  

15600 

1520 

870 

29150 

5510 

4390 

. 40 

864 

Yellow  fine 

sandy  loam . . . 

14180 

1300 

780 

30760 

5360 

4620 

500 

198 

Stony  loam 

(virgin) 

15600 

840 

480 

25040 

3420 

4300 

1520 

Swamp  and  Bottom-land 

Soils 

1323 

Red-brown  clay 

loam 

32320 

3090 

1830 

41200 

11780 

6430 

2390 

1331 

Deep  gray  silt 

loam 

12920 

1100 

580 

26580 

4860 

5860 

660 

1361.1 

Mixed  fine 

sandy  loam. . . 

13900 

1290 

650 

29480 

4990 

4910 

840 

1380 

River  sand 

11100 

520 

920 

18740 

5720 

10420 

21620 

Terrace  Soils 


Gray  clay 

37160 

3280 

1260 

39220 

12560 

11860 

1020 

Gray  silt  loam 
on  tight  clay. 

39280 

3360 

1440 

41860 

11880 

6360 

260 

By  comparing  the  data  in  Table  1 with  those  in  Table  A in  the  Appen- 
dix, the  relative  supply  of  the  different  essential  elements  of  plant  food  is 
very  easily  determined.  Thus  the  surface  soil  of  an  acre  of  the  yellow  silt 
loam  (the  most  extensive  soil  type  in  Hardin  county,  covering  most  of  the 
ordinary  hill  land)  contains  only  1250  pounds  of  total  nitrogen,  while  the 


4 


Soil  Report  No.  3 


[August, 


grain  crops  suggested  in  Table  A would  remove  from  the  soil  343  pounds 

during  one  rotation;  and  the  total  nitrogen  in  the  plowed  soil  (if  6 2/t, 

inches  deep)  would  meet  the  requirements  of  only  eight  such  crops  of  corn 
as  ought  to  be  grown  under  the  average  climatic  conditions  of  southern  Illi- 
nois. The  ratio  of  carbon  to  nitrogen  (about  10  to  1)  shows  that  the 

organic  matter  is  very  inactive,  and  consequently  that  the  liberation  of 
nitrogen  will  not  be  rapid.  The  other  upland  soils  of  the  county  are  not 
much  better  supplied  with  nitrogen ; and  too  great  emphasis  cannot  be  laid 
upon  the  importance  of  growing  legume  crops,  such  as  alfalfa,  clover,  cow- 
peas  and  soybeans,  which  if  infected  with  the  proper  nitrogen-fixing  bacteria 
have  -free  access  to  the  inexhaustible  supply  of  nitrogen  in  the  air. 
jt  On  the  other  hand,  there  are  some  difficulties  to  be  met  and  overcome 
if  the  most  valuable  legume  crops  are  to  be  grown  satisfactorily  on  these 
lands.  Thus,  all  of  these  upland  soils  are  markedly  sour  and  consequently 
they  not  only  contain  no  limestone,  but  require  applications  of  that  material 
to  correct  the  acidity  present. 

The  only  exception  to  this  is  the  small  area  of  yellow  fine  sandy  loam 
near  Rosiclare,  and  even  this  is  strongly  acid  in  the  subsurface  and  sub- 


Plate  1-  Wheat  in  Pot  Cultures;  Yellow  Silt  Loam  Soil  of  Hill  Land. 


soil,  the  small  amount  of  limestone  in  the  surface  soil  probably  being  due 
to  the  recent  additions  of  dust  blown  from  the  great  area  of  river  bed  to  the 
east  and  southwest,  which  is  exposed  to  the  action  of  the  wind  when  the 
river  is  low,  occasionally  for  weeks  at  a time.  Even  this  soil  should  receive 
liberal  applications  of  ground  limestone. 

Results  from  Pot-Culture  Experiments 

The  plant  food  element  which  limits  the  yield  of  cereal  crops  on  the 
common  upland  soil  is  nitrogen.  This  fact"  is  very  strikingly  illustrated 
by  the  results  from  pot-culture  experiments  reported  in  Table  3,  and  shown 
photographically  in  Plate  1. 

A large  quantity  of  the  typical  worn  hill  soil  was  collected  from  two 
different  places.  Each  lot  of  soil  was  thoroly  mixed  and  ten  4-gallon  jars 
were  filled  with  it.  Ground  limestone  was  added  to  all  except  the  first  and 
last  jars  in  each  set,  those  two  being  retained  as  control  or  check  plots. 
The  elements  nitrogen,  phosphorus,  and.  potassium  were  added  singly  and  in 
combination,  as  plainly  indicated  in  Table  3. 


Hardin  County 


5 


1912] 


Tabus  3 Crop  Yields  in  Pot-Culture  Experiments  on  Yellow  Silt  Loam  Hill 

Land  Soil 


Pot 

No. 

Soil  treatment  applied 

Wheat  yields 
(gramsperpot) 

Oat  yields 
(gramsperpot) 

1 

None 

3 

5 

2 

Limestone 

4 

4 

3 

Limestone,  nitrogen . . 

26 

45 

4 

Limestone,  phosphorus  

3 

6 

S 

Limestone,  potassium 

■ 3 

5 

6 

Limestone,  nitrogen,  phosphorus 

34 

38 

7 

Limestone,  nitrogen,  potassium 

33 

46 

8 

Limestone,  phosphorus,  potassium 

2 

5 

9 

Limestone,  nitrogen,  phosphorus,  potassium 

34 

38 

10 

■\T„ri  p 

■"  3 

5 

Average  yield  with  nitrogen 

32 

42 

Average  yield  without  nitrogen 

3 

5 

Average  gain  for  nitrogen 

29 

111 

As  an  average  the  nitrogen  applied  produced  about  eight  times  as  much 
as  the  yield  secured  without  the  addition  of  nitrogen.  While  there  are  some 
variations  in  yield  which  are  due,  of  course,  to  differences  in  the  individuality 
of  seed  or  other  uncontrolled  cause,  yet  there  is  no  doubting  the  plain  lesson 
taught  by  these  actual  trials  with  growing  plants.  Thus,  both  the  soil 
analysis  and  the  culture  experiment  agree  in  showing  that  the  element  nitro- 
gen myst  be  provided  for  the  improvement  of  this  soil. 

The  next  question  is,  Where  is  the  farmer  to  secure  this  much  needed 
nitrogen?  To  purchase  it  in  commercial  fertilizer  would  cost  too  much.  In- 
deed, the  cost  of  the  nitrogen  in  such  fertilizers  is  greater  than  the  value 
of  the  increase  in  crop  yields,  under  average  conditions.  On  the  other  hand, 
there  is  no  need  whatever  to  purchase  it,  because  the  air  contains  an  inexhaus- 
tible supply  of  nitrogen,  and  under  suitable  conditions  this  can  be  obtained  by 
the  farmer  direct  from  the  air,  not  only  without  cost,  but  with  profit  in 
the  getting;  for  clover,  alfalfa,  cowpeas  and  soybeans  have  pdwer  to  secure 
atmospheric  nitrogen,  provided  the  soil  contains  limestone  and  the  proper 
nitrogen-fixing  bacteria;  and  these  crops  are  worth  raising  for  their  own 
sake. 

In  order  to  get  further  information  along  this  line  an  experiment  with 
pot  cultures  was  conducted  for  several  years,  with  the  results  reported  in 
Table  4,  the  same  worn  hill  soil  being  used.  To  three  of  the  pots  (Nos.  3, 
6 and  9)  nitrogen  was  applied  in  commercial  form,  and  at  an  expense 
amounting  to  more  than  the  total  value  of  the  crops  produced.  In  three  other 
pots  (Nos.  2,  11  and  12)  a crop  of  cowpeas  was  grown  during  the  late  sum- 
mer and  fall,  and  these  were  turned  under  before  planting  wheat  or  oats. 
Pots  1 and  8 serve  for  important  comparisons. 

After  the  second  catch  crop  of  cowpeas  had  been  turned  under,  the  yield 
from  Pot  2 exceeded  that  from  Pot  3 ; and  in  the  subsequent  years  the  le- 
gume green  manures  produced,  as  an  average,  rather  better  results  than 
the  commercial  nitrogen.  These  experiments  confirm  those  reported  in 
Table  3,  in  showing  the  very  great  need  of  nitrogen  for  the  improvement 
of  this  soil ; and  they  also  show  that  the  nitrogen  need  not  be  purchased,  but 
that  it  can  be  obtained  from  the  air  by  growing  legume  crops  and  plowing 


6 


Soil  Report  No.  3 


[August, 


them  under  as  green  manure.  Of  course,  the  legume  crops  could  be  fed  to 
live  stock  and  the  resulting  farm  manure  returned  to  the  land;  but  this 
practice  is  not  so  good  for  the  soil,  altho  it  may  sometimes  be  more  profit- 
able; and  if  sufficiently  frequent  crops  of  legumes  are  grown  and  if  the 
farm  manure  produced  is  sufficiently  abundant,  and  is  saved  and  applied 
with  care,  this  soil  can  be  very  markedly  improved  by  live-stock  farming, 
as  well  as  by  green  manuring. 


Plate  2.  Wheat  in  Pot  Cultures;  Yellow  Silt  Loam  Soil  of  Worn  Hill  Land. 


Table  4 — Crop  Yields  in  Pot  Cultures,  Including  Nitrogen-Fixing  Green 
Manure  Crops:  Yellow  Silt  Loam  Hill  Land  (Grams  per  Pot) 


Pot 

No. 

Soil  treatment 

1903 

Wheat 

1904 

Wheat 

1905 

Wheat 

1906 

Wheat 

1907 

Oats 

1 

None 

■5 

4 

4 

4 

6 

2 

Limestone,  legume 

10 

17 

26 

19 

37 

11 

Limestone,  legume,  phosphorus 

14 

19 

20 

18 

27 

12 

Limestone,  legume,  phosphorus, 

potassium 

16 

20 

21 

19 

30 

3 

Limestone,  nitrogen 

17 

14 

15 

9 

28 

6 

Limestone,  nitrogen,  phosphorus 

26 

20 

18 

18 

30 

9 

Limestone,  nitrogen,  phosphorus, 

potassium 

31 

34 

21 

20 

26 

8 

Limestone,*  phosphorus,  potassium 

3 

3 

5 

3 

7 

Results  from  Field  Experiments  at  Vienna 

In  1902  a soil  experiment  field  was  established  on  the  worn  hill  land 
of  southern  Illinois,  near  Vienna,  in  Johnson  county;  and  the  results  of  nine 
years’  experiments  under  field  conditions  are  reported  in  Table  5. 

This  field  includes  three  divisions,  or  series,  with  five  plots  in  each  series. 
A three-year  rotation  of  wheat,  corn,  and  cowpeas  was  begun  on  this  field, 
but  because  of  local  interest  this  was  changed  to  corn,  wheat,  and  clover. 
When  the  clover  failed,  which  was  frequent,  cowpeas  were  substituted. 

During  the  first  three  years  the  entire  crop  of  cowpeas  was  plowed  under, 
except  on  Plot  1,  as  indicated  in  Table  5.  During  the  second  three  years  all 
crops  were  removed;  and  during  the  third  three-year  period  the  pods  of  the 
compeas  (small  yields  not  threshed),  and  all  grain  were  harvested  and  re- 
moved, while  the  pea  vines  or  clover,  and  the  wheat  straw  and  corn  stalks 
were  returned  to  the  land  (except  on  Plot  1,  from  which  all  crops  were  re- 


1912] 


Hardin  County 


7 


moved  and  nothing  returned).  Thus,  the  “crop  residues”  were  returned  in 
part  during  the  first  period,  not  at  all  during  the  second  period,  and  com- 
pletely only  during  the  third  period ; and  the  effect  of  plowing  under  all 
crop  residues  during  one  rotation  upon  the  crop  yields  of  the  next  rotation 
is  not  yet  shown  on  this  field. 

If  we  pass  over  the  first  three  years  required  to  get  the  rotation  and 
soil  treatment  underway,  we  still  have  the  records  of  six  years,  during 
which  time  6 crops  of  corn,  6 crops  of  wheat,  and  i crop  of  clover  hay 
were  harvested  and  weighed.  A study  of  Table.  5 will  show  that  the  land 
treated  with  ground  limestone  and  some  crop  residues  (Plot  3)  produced, 
during  the  six  years,  74  bushels  more  corn,  60  bushels  more  wheat,  and  i)4 
tons  more  hay  than  the  untreated  land. 

It  should  be  kept  in  mind  that  the  figures  showing  increase  in  crop 
yields  constitute  the  real  data  upon  which  all  subsequent  computations  must 
be  based.  The  work  of  the  investigator  is  to  conduct  the  experiment  and 
secure  the  data;  while  the  farmer  and  landowner  has  the  right  to  use  any 
prices  he  can  justify  for  his  locality  and  conditions,  and  these  prices  will 
vary  greatly,  not  only  in  different  years  and  seasons,  but  also  in  different 
localities.  Thus  the  average  price  of  corn  in  southern  Illinois  is  probably 
10  cents  a bushel  higher  than  in  the  corn  belt,  except  in  an  occasional  year 
when  southern  Illinois  may  produce  an  extra  good  crop  and  have  a surplus 
to  be  shipped  out. 

As  a rule  the  farmer  is  inclined  to  calculate  the  value  of  the  increase  in 
crop  yields  at  the  prevailing  prices;  while  the  computations  usually  made 
by  the  Experiment  Station  are  much  more  conservative.  At  current  prices 
for  produce,  say  60  cents,  a bushel  for  corn,  90  cents  for  wheat,  and  $15  a 
ton  for  hay,  the  increase  in  money  value  from  the  use  of  limestone  on  the 
Vienna  field  would  amount  to  $117,  which  is  $39  per  acre  for  the  six  years, 
or  $6.50  per  acre  per  annum  above  the  returns  for  the  same  crops  from  the 
untreated  land. 

By  comparing  Plots  2 and  3,  it  will  be  found  that  the  land  treated  with 
limestone  produced,  during  the  same  six  years,  64  bushels  more  corn,  39 
bushels  more  wheat,  and  1.1  tons  more  harvested  hay  than  the  land  other- 
wise treated  the  same.  At  the  prices  mentioned  these  increases  amount  to 
$90  from  three  acres,  or  $30  from  one  acre,  which  is  $5.00  an  acre  for  each 
year.  This  is  about  ten  times  the  necessary  average  annual  expense  for 
ground  limestone  in  permanent  systems.  Thus,  long-continued  investiga- 
tions have  shown  that  800  pounds  per  acre  is  about  the  average  annual  loss 
of  limestone.  At  $1.25  per  ton,  this  would  cost  50  cents  per  acre  per  annum. 

These  figures  indicate  a possible  gross  return  of  about  $to  for  every 
$1.00  necessarily  invested  in  ground  limestone  for  the  improvement  of  this 
soil,  which  represents  by  far  the  most  extensive  soil  type  in  the  seven 
southernmost  counties  of  Illinois.  Some  will  probably  insist  that  the  prices 
and  computations  used  above  are  reasonable  and  fair;  and  if  present  prices 
continue,  it  is  possible  that  investment  in  ground  limestone  may  ultimately 
pay  such  returns  if  the  seed  of  the  legume  crops  are  harvested  and  if  the 
full  system  of  manuring  with  crop  residues  and  catch  crops  is  followed  in 
the  best  crop  rotation;  but  in' Table  5 we  have  presented  the  more  con- 
servative figures.  ki- 

ln order  to  summarize  the  results  of  the  nine  years’  experiments,  the 
six  grain  crops  from  each  series  and  the  one  crop  of  clover  hay  harvested 


8 


Soil  Report  No.  3 


[August, 


from  the  200  series  (in  1907)  are  reduced  to  a money  basis,  in  which  corn 
is  figured  at  35  cents  a bushel,  oats  at  30  cents,  wheat  at  70  cents,  and  hay 
at  $6.00  a ton.  These  low  prices  are  used  in  order  to  avoid  any  possible  ex- 
aggeration of  the  value  of  the  increase  produced  by  the  soil  treatment 
applied.  The  prices  are  appreciably  below  the  ten-year  averages  for  Illi- 
nois, but  it  should  be  kept  in  mind  that  the  increase  produced  by  soil  treat- 
ment is  not  delivered  at  the  market  by  that  treatment,  but  only  ready . for 
the  harvest;  and  additional  expense  is  required  for  harvesting,  threshing, 
baling  and  storing  or  marketing.  The  yields  are  all  given,  and  anyone  can 
compute  the  value  of  the  increase  at  any  other  prices,  if  desired. 

About  9 tons  per  acre  of  ground  limestone  were  applied  in  1902.  The 
cost  of  this  is  figured  at  $1.25  per  ton.  This  is  somewhat  above  the  average 
cost  in  southern  Illinois. 

The  phosphorus  was  supplied  at  the  rate  of  25  pounds  per  acre  per  an- 
num in  200  pounds  of  steamed  bone  meal,  applied  at  the  rate  of  600  pounds 
every  three  years.  It  is  figured  at  10  cents  a pound  for  phosphorus,  or  at 
$25  a ton  for  steamed  bone.  The  average  cost  of  steamed  bone  is  now 
somewhat  higher;  and  where  farm  manure  or  green  manure  is  available  we 
advise  using  raw  rock  phosphate  in  place  of  steamed  bone,  the  raw  phos- 
phate being  just  as  rich  in  phosphorus  and  costing  in  southern  Illinois  less 
than  $8.00  per  ton  in  carload  lots. 

The  potassium  was  applied  at  the  rate  of  42  pounds  per  acre  per  annum 
in  100  pounds  of  potassium  sulfate.  The  potassium  sulfate  is  figured  at  $50 
per  ton,  or  potassium  at  6 cents  a pound.  As  shown  in  Table  2,  this  common 
upland  contains,  as  an  average,  more  than  30,000  pounds  of  potassium  in  the 
plowed  soil  of  an  acre  (6^3  inches  deep),  and  the  subsurface  and  subsoil 
are  still  richer,  so  that  the  potassium  problem  is  not  one  of  addition  but 
of  liberation;  and,  if  potassium  salts  are  applied  at  all  or  temporarily,  until 
more  vegetable  matter  can  be  grown  and  plowed  under,  then  we  would 
recommend  the  use  of  kainit  in  larger  amounts  and  at  less  expense,  rather 
than  potassium  sulfate,  for  reasons  explained  in  the  Appendix. 

It  should  be  understood  that  when  these  field  experiments  were  begun, 
we  had  but  very  little  information  concerning  the  composition  or  require- 
ments of  Illinois  soils.  We  used  steam  bone  meal  and  potassium  sulfate 
to  find  out  if  the  soil  needed  phosphorus  or  potassium.  It  was  known  that 
these  materials  furnish  those  elements  in  good  form.  On  many  experiment 
fields  established  more  recently  we  are  now  using  fine-ground  rock  phosphate 
with  very  good  results,  and  in  some  cases  we  are  also  making  trials  with 
kainit.  (See  Soil  Reports  Nos.  1 and  2 and  Circulars  116,  127,  149,  and 
157-') 

Taking  into  account  the  entire  period  of  nine  years,  it  will  be  seen  that,  at 
most  conservative  prices,  the  ground  limestone  has  alreadv  paid  back 
nearly  twice  its  actual  cost,  and  the  equivalent  of  about  one-half  of  the 
limestone  still  remains  in  the  soil  for  the  benefit  of  future  crops.*  It  is 

*On  the  Edgewood  experiment  field  in  Effingham  county  10  tons  per  acre  of  ground 
limestone  were  applied  in  1902.  At  the  end  of  ten  years  the  analysis  of  the  soil  showed 
that  8,370  pounds  of  limestone  still  remained  in  the  surface  stratum,  as  the  average  of 
eight  treated  plots ; while  the  acidity  of  the  subsurface  of  the  same  plots  averaged  2770 
pounds  less  fin  terms  of  limestone  required  to  neutralize  it)  than  the  average  of  eight 
untreated  half  plots,  and  the  acidity  in  the  surface  soil  of  the  untreated  land  corresponded 
to  1070  pounds  of  limestone  required.  Thus  the  total  difference  at  the  end  of  ten  years  is 
equivalent  to  6.1  tons  of  calcium  carbonate,  and  the  net  loss  has  been  3.9  tons  of  lime- 
stone, or  780  pounds  per  acre  oer  annum.  (These  averages  are  based  upon  analyses  in- 
volving twenty-four  determinations,  which  were  made  by  Mr.  C.  F.  Ferris,  B.S.,  as  part 
of  his  work  for  the  degree  of  Master  of  Science  in  Agronomy,  1912.) 


Hardin  County 


9 


1912 ] 


Table  5.— Crop  Yields  per  Acre  on  Vienna  Experiment  Field,  on  Common  Worn 
.Hill  Hand:  Yellow  Silt  Loam,  Unglaciated 


Soil  treatment 

None 

(except 

rotation) 

Crop 

residues 

Crop 

residues 

and 

limestone 

Crop 

residues, 

limestone, 

phosphorus 

Residues, 

limestone, 

phosphorus, 

potassium 

Plot  No 

101 

102 

103 

104 

105 

1902  Corn,  bu 

15.5 

13.3 

14.9 

12.5 

19.9 

1903  Corn,  bu 

9.3 

5.0 

8.3 

7.4 

11.6 

1904  Cowpeas 

removed 

turned 

turned 

turned 

turned 

190S  Wheat,  bu 

1.3 

10.8 

18.2 

25.6 

30.0 

1906  Cowpeas 

removed 

removed 

removed 

removed 

removed 

1907  Corn,  bu 

16.7 

17.8 

30.3 

37.1 

38.1 

1908  Wheat,  bu 

0 

0 

4.5 

8.3 

9.8 

1909  Cowpeas 

removed 

turned 

turned 

turned 

turned 

1910  Corn,  bu 

33.5 

35.4 

44.7 

46.6 

58.3 

Value  of  six  crops 

$27.16 

$32.59 

$50.26 

$59.99 

$72.63 

Increase  over  Plot  2 

$17.67 

$27.40 

$40  04 

Plot  No 

201 

202 

203 

204 

205 

1902  Oats,  bu  

19.1 

18.8 

19.8 

20.0 

31.7 

1903  Cowpeas 

removed 

turned 

turned 

turned 

turned 

1904  Wheat,  bu 

6.7 

7.1 

10.0 

14.8 

17.5 

1905  Corn,  bu  

37.5 

42.9 

61.9 

57.2 

56.5 

1906  Wheat,  bu 

3.8 

5.4 

17.9 

11.3 

15.0 

1907  Clover,  tons  

.65 

.81 

1.92 

2.56 

2.23 

1908  Corn,  bu 

35.2 

35.6 

43.9 

42.9 

50.6 

1909  Wheat,  bu  

4.6 

6.8 

9.6 

12.8 

11.3 

1910  Clover  . . 

removed 

turned 

turned 

turned 

turned 

Value  of  seven  crops 

$45.65 

$51.49 

$80.74 

$83.63 

$91.04 

Increase  over  Plot  2 

$29.25 

$32.14 

$39.55 

Plot  No 

301 

302 

303 

304 

305 

1902  Cowpeas 

removed 

turned 

turned 

turned 

turned 

1903  Wheat,  bu 

.4 

.6 

.7 

8.0 

11.0 

1904  Corn,  bu 

30.5 

35.5 

49.1 

49.4 

44.7 

1905  Cowpeas 

removed 

removed 

removed 

removed 

removed 

1906  Corn,  bu 

41.2 

40.6 

48.9 

40.9 

40.9 

1907  Wheat,  bu 

4.3 

6.1 

13.0 

13.6 

15.6 

1908  Cowpeas 

removed 

turned 

turned 

turned 

turned 

1909  Corn,  bu  

23.0 

24.9 

31.3 

32  6 

33.5 

1910  Wheat,  bu  

3.1 

8.7 

13.7 

14.4 

14.6 

Value  of  six  crops  . . . 

$38.61 

$46.13 

$64.44 

$68.22 

$70.53 

Increase  over  Plot  2 . . . . 

$18.31 

$22.09 

$24  40 

A era^e  of  three  series  . . 

$37.14 

$43.40 

$65 . 14 

$70.61 

$78.06 

Increase  over  Plot  2 

$21 . 74 

$27.21 

$34  66 

Cost  of  treatment 

$11.25 

$33.75 

$56.25 

possible,  too,  that  half  the  quantity  of  limestone  applied  at  the  beginning 
would  have  given  nearly  or  quite  as  good  results,  but  the  information  avail- 
able is  not  conclusive  as  to  the  initial  amount  of  limestone  to  apply  for  the 
most  profitable  results.  In  any  case  the  initial  application  should . be  consid- 
ered as  an  investment  to  be  added  to  the  value  of  the  land,  while  the  cost  of 
subsequent  necessary  applications  should  be  calculated  in  the  annual  exoense. 


10 


Soil  Report  No.  3 


[August, 


On  this  rolling  hill  land,  the  addition  of  $22.50  worth  of  steamed  bone 
meal  has  increased  the  crop  values  by  only  $5.47  in  nine  years;  and  the  fur- 
ther addition  of  $22.50  in  potassium  sulfate  has  produced  only  $7.45  in- 
crease in  the  value  of  the  crops  harvested,  at  the  prices  used  for  the  increase 
in  yields. 

Whether  a much  larger  use  of  organic  manures  will  ultimately  increase 
the  nitrogen  content  of  the  soil  to  a point  where  phosphorus  can  be  applied 
with  profit  on  these  hill  lands,  subject  to  rather  serious  surface  washing, 
seems  somewhat  doubtful ; and,  considering  the  fact  that  such  an  increase  in 
decaying  organic  matter  will  largely  increase  the  liberation  of  potassium 
from  the  enormous  supply  contained  in  the  soil,  it  seems  even  more  doubt- 
ful if  the  addition  of  potassium  will  ever  be  advisable  in  permanent  systems 
of  general  farming. 

Both  the  pot  cultures  and  the  field  experiments  agree  in  showing  that 
nitrogen  is  by  far  the  most  limiting  element  and  that  this  can  be  secured 
from  the  air  by  legume  crops  where  liberal  use  is  made  of  ground  limestone 
to  correct  the  acidity  of  the  soil;  and  of  course  the  limestone  also  furnishes 
the  element  calcium,  the  supply  of  which  in  this  soil  is  but  little  more  than 
one-tenth  as  great  as  the  supply  of  potassium,  while  the  combined  loss  by 
leaching  and  cropping  is  nearly  ten  times  greater  with  calcium  than  with  po- 
tassium, as  is  more  fully  explained  in  the  Appendix.  As  plant  food,  calcium 
is  especially  important  for  such  crops  as  clover.  (See  Table  A in  the 
Appendix.) 


Results  from  Field  Experiments  at  Raleigh 

The  Raleigh  experiment  field,  in  Saline  county,  is  located  on  the  gently 
undulating  timber  land  (yellow-gray  silt  loam),  which  is  also  the  second 
most  important  upland  soil  type  in  Hardin  county. 

Six  tons  per  acre  of  ground  limestone  were  applied  to  certain  plots  on 
the  Raleigh  field  in  the  fall  of  1909;  and  as  an  average  of  the  next  two 
years  (1910  and  1911)  the  limestone  increased  the  yields  per  acre  on  one  set 
of  plots  by  3.9  bushels  of  wheat,  by  .40  ton  of  hay  (cowpeas  or  clover), 
by  14. 1 bushels  of  oats,  and  by  13.4- bushels  of  corn;  while  on  another  set 
of  plots  the  average  increases  produced  by  limestone  were  4.8  bushels  of 
wheat,  9.3  bushels  of  oats,  and  12.0  bushels  of  corn.  In  this  second  series 
of  experiments  the  legume  crops  (except  the  seed)  are  plowed  under  for  soil 
improvement;  but  no  seed  was  produced  either  on  the  cowpeas  in  1910  or 
on  the  clover  in  1911,  and  consequently  the  effect  of  the  limestone  on  the 
legume  crops  was  not  determined  in  this  system. 

If  we  accept  the  average  of  the  two  series  and  compute  the  effect  from 
these  data  for  the  four-year  rotation,  we  find  a return  of  $12.20  from  an 
investment  of  $7.50  in  limestone;  and  the  limestone  applied  to  the  soil  is 
sufficient  to  last  for  more  than  to  years.  These  data  strongly  support  those 
from  the  Vienna  field  in  showing  the  positive  value  and  need  of  limestone 
in  the  very  beginning  of  improvement  for  these  acid  upland  soils  of  southern 
Illinois. 

The  work  at  Raleigh  has  been  carried  on  for  only  two  years,  and  the 
organic  manures  thus  far  produced  and  returned  to  the  soil  are  too  meager 
to  produce  results  from  which  trustworthy  conclusions  can  be  drawn  con- 
cerning either  the  nitrogen  secured  or  the  phosphorus  and  potassium  liber- 
ated; but  that  the  addition  of  fine-ground  raw  rock  phosphate  in  connec- 


Hardin  County 


11 


1912] 


Table  6 Fertility  in  the  Soils  of  Hardin  County,  Illinois 


Average  pounds  per  acre  in  4 million  pounds  of  subsurface  soil  (about  6 % to  20  inches) 


Soil 

Total 

Total  I 

Total 

Total 

Total 

Total 

Lime- 

Lime- 

type 

Soil  type 

organic 

nitro- 

phos- 

potas- 

magne- 

calci- 

stone 

stone 

No. 

carbon 

gen  | 

phorus 

sium  I 

' sium 

um 

present 

required 

Upland  Timber  Soils 


135 

Y ellow  silt  loam 

9670 

1390 

1930 

71340 

19780 

7650 

8910 

134 

Yellow-gray  silt 

loam 

13600 

1500 

1820 

64320 

15000 

8060 

2780 

864 

Yellow  fine 

sandy  loam . . . 

12920 

1640 

1960 

67640 

17560 

7840 

5000 

Swamp  and  Bottom-land  Soils 


1323 

Red-brown  clay 

9720 

loam  . 

35120 

3960 

3180 

86200 

25240 

3220 

1331 

Deep  gray  silt 

loam 

10480 

960 

880 

55280 

11640 

11400 

1361.1 

Mixed  fine 

sandy  loam . . . 

28460 

2580 

1220 

56860 

8960 

9860 

2000 

1380 

River  sand.  . . 

18960 

760 

1840 

33640 

10640 

20080 

30760 

Terrace  Soils 


1516 

Gray  clay 
Gray  silt  loam 

43920 

4160 

2080 

77200 

28200 

23240 

40 

1530 

on  tight  clay 

2' 400 

2080 

1800 

88720 

34480 

13160 

2800 

Table  7. — Fertility  in  the  Soils  of  Hardin  County,  Illinois 
Average  pounds  per  acre  in  6 million  pounds  of  subsoil  (about  20  to  40  inches) 


Soil 

Total 

Total 

Total 

Total 

Total 

Total 

Lime- 

Lime- 

type 

Soil  type 

organic 

nitro- 

phos- 

potas- 

magne- 

calci- 

stone 

stone 

No. 

carbon 

gen 

phorus 

sium 

sium 

um 

present 

required 

U pland  Timber  Soils 


135 

Y ellow  silt  loam 

8060 

1310 

2700 

109070 

30670 

19580 

10060 

134 

Yellow-gray  silt 

loam 

10020 

1620 

2610 

94530 

25830 

12330 

13950 

864 

Y ellow  fine 

sandy  loam  . . 

8400 

1500 

3240 

107400 

29580 

13320 

10080 

Swamp  and  Bottom-land  Soils 


1323 

Red-brown  clay 

loam 

35910 

4080 

4440 

130800 

36210 

14610 

4560 

1331 

Deep  gray  silt 

loam  

12300 

1380 

1440 

86340 

21600 

17760 

1361.1 

Mixed  fine 

sandy  loam  .. 

41550 

3990 

2370 

78180 

13590 

17100 

3000 

1380 

River  sand  . • ■ • 

24480 

660 

1740 

47160 

13080 

24960 

32880 

Terrace  Soils 


1516 

Gray  clay  ...  . 

33480 

3000 

2460 

106200 

43560 

36180 

60 

1530 

Gray  silt  loam 

on  tight  clay  . 

31200 

3420 

2880 

132660 

51120 

19980 

1500 

tion  with  organic  manures  (farm  manure,  green  manures  or  crop  residues) 
will  prove  profitable  on  these  undulating  or  gently  rolling  upland  soils  is 
very  certain  from  the  results  already  secured  from  other  experiment  fields. 
(See  Soil  Reports  Nos.  1 and  2,  and  Circulars  116,  149,  and  157.)  On 
the  other  hand,  the  first  step  in  the  upbuilding  of  these  soils  is  the  liberal 


12 


Soil  Report  No.  3 


[August, 


wse  of  limestone  in  connection  with  clover  or  other  legume  crops  grown  in 
rotation  with  corn  and  other  grains;  and  when  the  legume  crops  or  farm 
manures  are  available  to  plow  under  in  significant  amount  then  is  the  time 
to  begin  the  application  of  phosphate,  to  be  turned  under  in  intimate  con- 
tact with  the  decaying  organic  matter.  Where  used  in  this  way  on  very 
similar  land  at  the  Ohio  Agricultural  Experiment  Station,  as  an  average 
of  duplicate  tests  on  three  different  series  of  plots  during  a period  of  fifteen 
years,  every  dollar  invested  in  raw  phosphate  paid  back  $7.42,  counting  $7.50 
per  ton  for  the  phosphate,  35  cents  a bushel  for  corn,  70  cents  for  wheat, 
and  $6.00  a ton  for  clover  hay;  while  in  a corresponding  experiment  every 
dollar  invested  in  acid  phosphate  (at  $15  per  ton)  paid  back  $3.69.  (See 
Illinois  Circulars  116,  127  and  130  for  more  details  of  these  valuable  Ohio 
experiments. ) 

No  field  experiments  have  been  conducted  on  the  less  extensive  soil  types, 
but  their  composition  is  shown  in  Tables  2,  6 and  7,  and  their  general  char- 
acteristics and  meeds  are  discussed  for  each  individual  type  in  the  following 
pages. 

The  Subsurface  and  Subsoil 

In  Tables  6 and  7 are  recorded  the  amounts  of  plant  food  per  acre  in 
the  subsurface  (6 ^ to  20  inches)  and  subsoil  (20  to  40  inches),  but  it 
should  be  remembered  that  these  supplies  are  of  little  value  unless  the  top 
soil  is  kept  rich,  except  that  they  serve  as  a source  of  renewal,  even  by 
very  slight  surface  washing,  for  any  element  which  they  contain  in  great 
abundance,  as  is  the  case  with  potassium ; and  where  much  surface  soil  is 
removed  by  erosion,  as  on  the  rolling  hill  land,  even  the  supply  of  phos- 
phorus is  renewed  from  the  substrata  in  amounts  which  may  equal  or  ex- 
ceed the  requirements  of  the  crops  that  are  grown  where  nitrogen  is  so 
commonly  the  limiting  element. 

Among  the  most  important  information  contained  in  Tables  6 and  7 is 
that  the  upland  soils  are  even  more  strongly  acid  in  the  subsurface  and 
subsoil  than  in  the  surface  stratum,  thus  emphasizing  the  importance  of  put- 
ting plenty  of  limestone  in  the  surface  soil  to  neutralize  the  acid  moisture 
which  rises  from  the  lower  strata  by  capillary  action  during  the  periods  of 
partial  drouth,  which  are  also  critical  periods  in  the  life  of  such  plants  as 
clover. 

In  the  case  of  the  less  rolling  upland  (vellow-gray  silt  loam)  where 
surface  washing  is  not  marked,  the  basic  elements  have  been  leached  out  and 
replaced  with  acid  to  such  a depth  that  the  subsoil  is  even  more  strongly  acid 
than  the  subsurface,  altho  this  is  not  the  case  with  the  yellow  silt  loam;  and. 
where  very  marked  recent  erosion  has  occurred,  almost  unleached  subsoil 
containing  limestone  is  sometimes  exposed. 


Hardin  County 


13 


1912] 


INDIVIDUAL  SOIL  TYPES 


(a)  Upland  Timber  Soils 
Yellow  Silt  Loam  (135) 

This  is  by  far  the  most  common  type  in  the  county,  occupying  70.5  per- 
cent of  the  area,  or  120  square  miles.  The  soil  was  formed  from  material 
derived  from  glacial  or  alluvial  formations,  carried  by  the  winds  and  de- 
posited at  all  altitudes.  The  average  depth  of  this  loess  or  wind-blown  ma- 
terial is  not  far  from  ten  feet.  The  residue  from  the  decay  of  the  rocks 
has  been  so  completely  buried  that  it  forms  ordinarily  no  part  of  the  soil. 
This  residual  material  may  be  seen  in  some  cuts  as  a reddish  iclay,  fre- 
quently mixed  with  angular  cherty  or  flinty  pebbles.  The  topography  of 
this  type  varies  from  rolling  to  very  hilly  and  includes  some  land  that 
should  not  be  cultivated  at  all  or  that  may  be  farmed  only  with  the  greatest 
care  to  avoid  loss  by  erosion.  Much  of  this  type  has  been  abandoned  agri-  +* 
culturally  already,  and  some  of  it  should  never  have  been  cleared  of  its 
protecting  forests.  It  frequently  occurs  that  the  northern  slopes  are  abrupt, 
while  those  toward  the  south  are  more  gradual  and  may  be  cultivated  fairly 
well. 

In  the  part  of  the  county  in  the  vicinity  of  Elizabethtown  and  Cave-in- 
Rock  the  rolling  topography  is  due  in  part  to  the  many  sink-holes  formed 
by  the  solution  of  the  underlying  limestone.  These  depressions  vary  in 
size  from  about  30  feet  to  several  hundred  feet  in  diameter  and  perhaps 
from  10  to  40  feet  deep.  They  drain  naturally  into  underground  channels, 
but  in  many  cases  these  drainage  outlets  have  been  stopped  and  sinkhole 
ponds  result.  About  three  miles  northwest  of  Cave-in-Rock  this  obstructed 
drainage  has  resulted  in  the  formation  of  a lake  that  covers  an  area  of  100 
acres  or  more,  varying  in  extent  with  the  time  of  year  and  the  amount  of 
rainfall.  (The  soil  area  shown  as  1361.1  shows  the  limit  of  the  lake  when 
at  its  greatest  size.) 

The  surface  soil  of  the  common  hill  land,  o to  62/z  inches,  is  a light  «* 
brown  to  yellow  silt  loam  varying  with  the  amount  of  organic  matter,  which 
in  turn  is  dependent  to  a large  extent  upon  the  amount  of  erosion.  Usually 
the  latter  color  prevails.  The  organic  matter  content  is  very  low  in  this  tvpe, 
much  too  low  for  a fertile  soil,  about  1.1  per  cent,  as  an  average,  in  the 
surface  soil,  or  only  11  tons  per  acre.  From  its  yellow  color  this  type  is 
commonly  called  a clay  soil;  but  it  contains  from  25  to  30  percent  of  fine 
sand,  and  much  the  larger  part  of  the  remaining  70  to  75  percent  is  silt, 
thus  rendering  it  porous  and  mealy  and  easily  worked ; whereas  true  clay  is 
plastic  or  gummy  and  very  difficult  to  work.  The  surface  soil  is  usually  dis- 
tinguished from  the  subsurface  by  a difference  in  color  due  to  the  still  lower 
organic  content  of  the  subsurface  soil. 

The  subsurface  stratum  is  somewhat  variable  in  thickness,  depending 
upon  the  amount  of  erosion  that  has  taken  place,  the  average  being  about 
8 or  9 inches.  In  some  spots  it  is  practically  absent,  while  in  others  it  is 
from  10  to  12  inches  in  thickness.  It  is  a light  vellow  silt  loam,  mealy,  por- 
ous, and  pulverulent,  the  phvsical  composition  being  a little  finer  than  in  the  ^ 
surface.  The  average  organic  matter  content  is  .4  percent,  or  only  8 tons 
per  acre  for  4 million  pounds  of  soil  (6^3  to  20  inches). 


Soil  Report  No.  3 


[August, 


Plate;  3.  Young  Grove  of  Black  Locust  Trees  on  Rolling  Hill  Land  in 
Johnson  County,  Illinois.  (Grown  by  J.  C.  B.  Heaton.) 

The  subsoil,  extending  from  the  subsurface  stratum  to  a depth  of  40 
inches,  is  a yellow  silt  or  slightly  clayey  silt.  Gray  blotches  of  unoxidizecl 
material  often  occur  in  the  deeper  subsoil.  This  stratum  is  more  compact 
and  not  quite  so  porous  as  those  above  it,  yet  sufficiently  pervious  to  allow 
water  to  pass  thru  it. 

The  variations  of  this  type  are  produced  chiefly  by  erosion.  It  represents 
varying  degrees  of  fertility.  In  some  places  very  little  washing  has  occurred, 
in  others  the  surface  has  been  largely  removed,  while  in  others  the  subsoil 
may  be  exposed  as  unproductive  yellow  “clay  points.” 

Of  most  importance  in  the  management  of  this  type  is  preventing  much 
loss  by  washing.  This  process  has  gone  on  to  such  an  extent  that  a large 
percentage  of  the  type  has  been  agriculturally  abandoned,  and  so  far  not  only 
has  nothing  been  done  to  reclaim  the  abandoned  land,  but  very  little  has 
been  done  to  prevent  further  loss  on  land  now  under  cultivation.  Erosion 
occurs  as  sheet-washing  and  gullying.  Ordinarily  we  do  not  think  of  sheet- 
washing as  doing  very  much  damage,  but  it  is  really  the  form  that  does  the 
greatest  amount  of  injury.  Gullying  results  in  the  absolute  ruin  of  small 
areas,  but  sheet  washing  reduces  the  productive  capacity  of  large  areas  to 
such  a point  that  not  only  profitable  crops  cannot  be  grown,  but  even  the 


Hardin  County 


IS 


1912] 


Puate  4.  Grove  of  Locust  Trees  About  Twenty-five  Years  Ol,d  on  Routing 
Hied  Land  in  Johnson  County,  Ieeinois.  (Grown  by  J.  C.  B.  Heaton.) 

growth  of  crops  large  enough  to  pay  for  the  raising  becomes  impossible. 
Every  means  should  be  taken  to  prevent  this  loss. 

Steep  gullied  slopes  probably  never  can  be  reclaimed  with  profit  for 
cropping  purposes  at  the  present  average  prices  for  labor  and  farm  produce. 
They  were  originally  forested  and  these  forests  should  never  have  been  en- 
tirely removed.  It  was  the  only  thing  that  made  these  lands  valuable  in 
the  first  place,  and  to  make  them  of  any  future  value  they  should  be  re- 
forested. This  has  been  done  in  a few  cases  with  excellent  success.  The  ac- 
companying illustrations  show  such  results.  The  black  locust  can  be  used 
most  successfully  for  this  purpose  as  it  is  largely  independent  of  the  supply 


16 


Soil  Report  No.  3 


[August, 


of  nitrogenous  organic  matter  in  the  soil.  Where  not  in  forest  the  steep 
land  should  be  kept  in  pasture  as  much  as  possible,  and  if  plowed  should  be 
cropped  for  only  one  or  two  years  and  then  reseeded  to  pasture.  Live  stock 
is  indispensable  to  farming  on  this  type  of  soil. 

Sheet  washing  on  the  moderate  slopes  may  be  prevented  to  a great  extent 
by  the  following  methods : 

( 1 ) By  increasing  the  organic  matter  content,  thus  rendering  the  soil 
more  porous,  and  binding  the  soil  particles  together.  This  can  be  done  by 
adding  farm  manure,  plowing  under  stubble,  straw,  cornstalks,  and  legume 
crops,  such  as  clover  and  cowpeas. 

(2)  By  deep  plowing  to  increase  the  absorption  of  water  and  diminish 
the  run-off.  Ten  inches  of  loose  soil  will  readily  absorb  2 inches  of  rainfall 
without  run-off.  Plowing  should  be  done  seven  to  ten  inches  deep. 

(3)  By  contour  plowing.  Plowing  in  this  state  is  often  done  up  and 
down  the  hill,  producing  dead  furrows  that  furnish  excellent  beginnings  for  , 
gullies.  Even  the  little  depressions  between  furrows  will  aid  washing.  On 
land  subject  to  serious'  washing,  plowing  should  always  be  done  across  the 
slope  on  the  contour,  so  that  water  will  stand  in  the  furrow  without  run- 
ning in  either  direction.  Every  furrow  will  act  as  an  obstruction  to  the 
movement  of  water  down  the  slope,  thus  diminishing  the  velocity  of  the 
water,  facilitating  absorption,  and  diminishing  the  amount  of  run-off  and 
the  power  of  the  water  to  do  washing. 

(4)  By  the  use  of  cover  crops  to  hold  the  soil  during  the  winter  and 
spring.  Rye  is  a fairly  good  cover  crop  to  sow  in  the  corn  during  the  late 
summer  or  early  fall.  Wheat,  especially  when  seeded  late,  is  a poor  crop  to 
grow  on  rolling  land  because  it  does  not  usually  make  sufficient  growth  to 


Table  8. — Crop  Yields  per  Acre  from  Reclaimed  Abandoned  Hill  Hand: 
Vienna  Experiment  Field 


Year 

Field  1 

Field  2 

Field  3 

Field  4 

1906 

1907 

1908 

Corn  20.4  bu. 
Cowpeas  turned 
Wheat  7.9  bu. 

Cowpeas  turned 
Wheat  9 6 bu. 
Clover .77  ton 

Clover  1.00  ton 
Corn  33,5  bu. 

Corn  24.4  bu. 
Cowpeas  turned 

1909 

1910 

1911 

Clover .60  ton* 
Corn  38.6  bu. 

Corn  37.8  bu. 
Cowpeas  turned 
Wheat  17  6 bu. 

Cowpeas  turned 
Wheat  15.6  bu. 

Wheat  8.8  bu. 
Clover  1.53  tons 
Corn  32.8  bu. 

Average  Yields  of  Crops  Grown 


Corn 

Wheat 

Clover 

1906-1908 

25  1 bu. 

8.8  bu. 

.89  ton 

1909-1911 

36.4  bu. 

. 14.0  bu. 

1.07  tons 

*The  yield  of  clover  for  1909  is  estimated,  the  weights  not  having  been  taken 
because  of  a misunderstanding. 


afford  a good  protection  to  the  soil  during  winter.  Of  course  both  rye  and 
wheat  invite  the  development  of  chinch  bugs.  A mixture  of  winter  vetch, 
and  clover,  with  a few  cowpeas,  seeded  at  the  time  of  the  last  cultivation  of 
the  corn,  gives  results  in  favorable  seasons. 

Experiments  in  methods  of  preventing  soil  erosion  are  being  carried  on 
in  Johnson  county  near  Vienna  on  abandoned  land  purchased  in  1906 
by  the  University  of  Illinois.  In  addition  to  the  methods  above  described, 
two  ions  per  acre  of  ground  limestone  are  applied  every  four  years.  The 


Hardin  County 


17 


A912] 

results  show  that  this  land  may  be  reclaimed  and  made  to  produce  fair  crops, 
as  is  shown  in  Table  8. 

These  results  show  that  fairly  good  crops  may  be  grown  upon  this  aban- 
doned land  if  proper  care  is  taken  to  reduce  washing,  and  if  use  is  made 
of  ground  limestone  and  a good  crop  rotation.  The  results  also  indicate 
that  the  crop  yields  tend  to  increase  under  this  system.  (See  also  Tables 
3,  4 and  5.) 

Alfalfa  may  well  be  one  of  the  crops  grown  in  this  type  of  soil.  Note  the 
suggested  rotation  and  directions  under  Yellozv-Gray  Silt  Loam  and  Yellozv 
Fine  Sandy  Loam. 


YellouyGray  Silt  Loam  (134) 

This  type  occurs  only  in  limited,  somewhat  isolated  areas  over  the  county, 
usually  surrounded  by  yellow  silt  loam  (135).  The  type  covers  10.5  square 
miles,  or  6.17  percent  of  the  area  of  the  county.  It  comprises  the  less  roll- 
ing areas  of  the  upland  and  furnishes  some  good  agricultural  land.  The 
topography  varies  from  slightly  undulating  to  rolling.  All  of  this  land  may 
be  cultivated  but  in  some  places  where  it  grades  toward  the  yellow  silt  loam 
care  must  be  taken  to  prevent  washing.  Its  origin  is  the  same  as  the  yellow 
silt  loam  (135). 

The  surface  soil,  o to  6Y3  inches,  is  a yellow  to  yellowish  gray  silt 
loam,  porous,  mealy,  and  pulverulent.  Its  good  physical  condition  is  due  to 
the  considerable  percentage  of  fine  sand  that  it  contains.  The  organic  matter 
content  is  low,  the  average  being  1.35  percent — but  slightly  higher  than 
the  yellow  silt  loam. 

The  subsurface  stratum,  varying  from  about  8 to  12  inches  in  thickness, 
is  a yellow  to  grayish  yellow  silt  loam  distinguished  from  the  surface  soil 
by  its  lighter  color.  Its  physical  composition  is  very  much  like  the  surface 
except  that  there  is  less  organic  matter,  only  .56  percent. 

The  subsoil  from  the  subsurface  to  a depth  of  40  inches  is  a compact 
yellow  or  grayish  yellow  silt  or  clayey  silt,  plastic  when  wet.  Concretions  of 
iron  are  found  in  the  subsurface  and  subsoil  in  the  more  nearly  level  areas. 

While  the  type  is  one  of  the  best  in  the  county,  the  supply  of  organic 
matter  should  be  increased  to  keep  the  soil  in  good  physical  condition  and 
thus  prevent  washing. 

At  least  2 tons  per  acre  of  ground  limestone  should  be  applied,  and  4 
or  5 tons  would  be  even  more  profitable  for  the  initial  application,  after 
which  about  2 tons  every  four  or  five  years  will  be  sufficient  to  keep  the  soil 
sweet.  Legume  crops  should  be  grown  in  a good  rotation,  such,  for  exam- 
ple, as  corn,  cowpeas,  wheat,  and  clover,  on  four  fields,  with  alfalfa  on  a 
fifth  field.  After  five  years  the  alfalfa  field  may  be  broken  up  and  used  for 
the  four-year  rotation,  one  of  the  four  fields  being  seeded  to  alfalfa  for 
another  five-year  period.  (See  also  Yellow  Fine  Sanclv  Loam,  page  18.) 

The  organic  matter  and  nitrogen  should  be  increased  either  by  using 
all  crops  except  the  wheat  for  feed  and  bedding,  saving  and  retaining  the 
manure  produced,  or  by  selling  only  grain  or  seed  and  some  alfalfa  hay 
and  plowing  under  all  other  crops  and  residues. 

About  1,000  pounds  per  acre  of  very  finely  ground  r-ock  phosphate  should 
be  plowed  under  with  the  organic  matter  every  four  or  five  years,  and  the 
initial  application  may  well  be  at  least  1 ton  per  acre.  Temporarily  some  use 
may  well  be  made  of  steamed  bone  meal,  as  by  drilling  about  200  pounds 


18 


Soil  Report  No.  3 


[August, 


per  acre  when  seeding  wheat  on  land  where  no  adequate  provision  has  been 
made  for  the  decaying  organic  matter  required  to  liberate  phosphorus  from 
the  raw  phosphate  used  in  the  more  profitable  permanent  systems  of  soil 
improvement. 

In  composition  this  type  of  soil  resembles  that  of  the  gray  silt  loam 
prairie  (330)  described  in  Soil  Report  No.  1,  and  the  reader’s  attention  is 
called  to  Tables  3,  6 and  7 in  that  report,  showing  the  composition  of  the 
prairie  soil  and  the  results  obtained  from  field  experiments  conducted  in  that 
soil  at  DuBois  and  Fairfield.  The  Raleigh  experiment  field,  referred  to  in 
the  preceding  pages,  is  located  in  the  yellow-gray  silt  loam,  and,  tho  recently 
established,  is  already  beginning  to  show  valuable  results  from  proper  meth- 
ods of  soil  improvement. 

Yellow  Fine  Sandy  Loam  (864) 

Only  a small  area  of  this  type  is  found  in  the  county,  amounting  to  294 
acres.  It  occurs  on  the  point  extending  southward  in  a bend  of  the  Ohio 
river,  thus  furnishing  a place  of  deposit  for  the  material  picked  up  by  the 
wind  sweeping  over  the  bottom  land  when  exposed  at  times  of  low  water. 

The  area  is  small  and  very  rolling  so  that  very  little  is  under  cul- 
tivation. In  some  counties  along  the  Mississippi  river  this  type  occurs  in 
very  extensive  areas.  Where  cultivated  it  should  be  protected  from  excessive 
surface  washing,  and  liberal  use  should  be  made  of  ground  limestone  and  or- 
ganic matter.  The  soil  is  especially  adapted  to  the  growing  of  alfalfa  when 
well  inoculated  and  sweetened  with  about  5 tons  per  acre  of  limestone;  but, 
in  order  to  give  the  alfalfa  a good  start,  a moderate  application  of  farm 
manure  or  500  to  1000  pounds  per  acre  of  acid  phosphate  (or  still  better, 
both  manure  and  acid  phosphate)  should  be  plowed  under.  After  the  al- 
falfa is  well  started  it  roots  very  deeply  and  becomes  almost  independent 
of  the  top  soil,  except  with  respect  to  limestone. 

Stony  Loam  (198) 

This  type  occurs  on  the  slopes  of  hills  and  ridges  where  erosion  has  re- 
moved most  of  the  loess  and  residual  material,  to  a large  extent  leaving 
a mixture  of  these  and  stones  to  constitute  the  soil.  The  stones  vary  from, 
a few  inches  to  several  feet  in  diameter.  It  comprises  17.05  square  miles, 
or  10  percent  of  the  entire  area.  It  is  of  little  agricultural  value,  its  only 
use,  aside  from  growing  of  forests,  being  for  pasture. 

Rock  Outcrop  (199) 

This  can  hardly  be  considered  a type  of  soil  but  may  have  some  value 
as  a source  of  limestone  for  use  on  acid  soils. 

The  outcrop  occurs  frequently  as  perpendicular  ledges,  and  the  horizontal 
width  is  often  somewhat  exaggerated  in  order  to  show  the  boundary  lines  on 
the  soil  map. 

(b)  Swamp  and  Bottom-land  Soils 
Rcd-Brozvn  Clay  Loam  (1323) 

This  type  comprises  the  greater  amount  of  the  bottom  land  along  the 
Ohio  river,  the  total  area  being  3.16  square  miles  or  1.86  percent  of  the  area 
of  the  county.  Two  large  areas  occur,  one  in  the  southwest  and  the  other 


Hardin  County 


19 


‘912] 


in  the  southeast.  A few  small  areas  occur  at  the  mouths  of  some  of  the 
small  creeks  that  flow  into  the  Ohio.  This  type  is  formed  by  deposit  from 
the  flood  waters  of  the  Ohio  river  and  has  been  found  in  all  of  the  counties 
surveyed  that  border  on  that  river. 

The  topography  varies  from  almost  flat  to  gently  undulating,  the  undu- 
lations being  due  to  the  narrow  but  elevated  ridges  and  depressions  formed 
by  currents  during  overflow.  The  drainage  is  not  always  good,  there  being 
many  low,  wet  places  in  which  the  crop  may  be  badly  damaged. 

The  surface  soil,  o to  6^3  inches,  is  a yellow  to  reddish  brown  clay 
loam,  plastic,  but  granular  under  proper  conditions.  Like  all  clays  and  clay 
loams,  it  will  become  hard  and  intractable  if  worked  when  wet,  due  to  pud- 
dling or  the  breaking  down  of  the  granules.  This  will  be  restored  by  the 
moistening  and  drying  produced  by  showers  or  by  freezing  and  thawing. 

The  amount  of  organic  matter  varies  from  2)4  to  3)4  percent,  with  an 
average  of  about  2^  percent.  The  physical  composition  varies  somewhat, 
the  heavier  phase  being  near  the  bluff  and  on  the  lower  ground,  and  the 
lighter  or  more  sandy  near  the  river. 

The  subsurface,  62/$  to  20  inches,  is  not  distinctly  separated  from 
either  the  surface  or  subsoil.  The  color  gradually  becomes  lighter  with 
depth,  due  to  the  smaller  amount  of  organic  matter,  which  is  1.5  percent  in 
this  stratum. 

The  subsoil,  20  to  40  inches,  is  a yellowish  brown  clay  loam,  tough  and 
plastic,  yet  pervious  to  water.  It  varies  slightly  with  the  topography,  the 
lower  areas  having  a heavier  subsoil. 

This  soil  is  more  difficult  to  manage  than  a lighter  soil,  owing-  to  the 
danger  of  puddling  if  worked  when  too  wet  and  to  its  cloddy  character 
when  dry.  This  type  cracks  rather  badly  owing  to  the  property  of  shrink- 
age which  clay  possesses  to  such  a degree.  Corn  is  the  chief  crop,  but  where 
protected  from  overflow  other  crops  can  be  grown.  The  soil  is  rich  in 
mineral  plant  food,  but  legumes  should  be  grown  in  the  rotation  where  the 
land  does  not  overflow. 


Deep  Gray  Silt  Loam  (1331) 

This  type  is  found  in  some  of  the  wider  bottoms  of  the  small  streams, 
mostly  near  their  mouths.  It  is  formed  from  material  washed  from  the  hills. 
It  seems  to  be  an  older  deposit  than  the  mixed  sandy  loam  (1361.1)  and  is 
occasionally  a little  higher  bottom  land.  Since  its  deposition  the  iron  has  been 
deoxidized,  and  as  a result  the  color  has  been  changed  from  a yellow  or 
brownish  to  a gray  or  light  drab.  The  topography  is  flat  to  gently  undulat- 
ing. The  extent  of  this  type  in  the  county  is  768  acres,  constituting  only 
.65  percent  of  the  total  area  of  the  county. 

The  surface,  o to  6^6  inches,  is  a gray  silt  loam  varying  to  a yellowish 
gray  silt  loam  or  fine  sandy  loam.  Iron  concretions  are  usually  found  upon 
the  surface  and  mixed  with  the  surface  and  subsurface  strata.  All  of  this 
type  contains  considerable  fine  sand,  giving  it  an  almost  ideal  physical  com- 
position. It  is  very  low  in  oragnic  matter,  having  only  about  1 percent. 

The  subsurface,  6^4  to  20  inches,  is  a gray  silt  loam,  friable,  pulverulent, 
but  compact  and  not  very  pervious,  especially  upon  the  higher  and  apparently 
older  areas. 

The  subsoil  is  mostly  a gray  silt,  but  varies  from  this  to  a gray  silty 
clay,  compact,  tough  and  almost  impervious,  resembling  the  subsoil  of  the 
gray  silt  loam  on  tight  clay  on  the  more  elevated  parts  of  the  bottom  land 


2kj 


Soil  Report  No.  3 


[August, 


The  type  is  drained  poorly  as  a rule,  and  better  drainage  with  the  addi- 
tion of  organic  matter  are  the  first  requirements  for  improvement,  altho  it 
will  be  necessary  to  add  limestone  to  get  the  organic  matter  by  the  growing 
of  legumes,  because  of  the  acidity  of  the  soil  and  subsoil.  Where  protected 
from  overflow  phosphorus  should  also  be  applied  in  systems  of  permanent 
improvement. 


Mixed  Fine  Sandy  Loam  (1361.1) 

This  type  is  found  along  the  small  stream  of  the  county  as  bottom  land, 
varying  in  width  from  a few  rods  to  a half  mile,  altho  in  these  wider  places 
the  soil  may  grade  toward  the  deep  gray  silt  loam.  The  material  forming 
this  type  has  been  rather  recently  washed  from  the  surrounding  hills,  the 
finer  particles  being  carried  into  the  Ohio  river,  while  the  coarser  are  de- 
posited in  these  bottoms. 

The  topography  is  flat  to  gently  undulating,  the  undulations  being  due 
to  the  old  system  channels  and  those  produced  during  floods.  Natural  drain- 
age is  usually  good.  In  some  places  the  type  is  underlain  by  gravel. 

The  total  area  of  the  type  is  8074  acres  or  7.4  percent  of  the  entire  area 
of  the  county. 

The  surface,  subsurface  and  subsoil  are  practically  the  same,  the  chief 
difference  being  in  the  amount  of  organic  matter  in  some  places,  altho  this 
does  not  vary  as  much  as  might  be  supposed.  The  amount  varies  from  1 to 
1^2  percent  in  the  surface  soil.  This  is  one  of  the  best  types  in  the  county, 
producing  fair  crops  of  corn,  wheat  and  cowpeas. 

As  a rule  this  soil  is  not  acid,  more  or  less  of  the  material  being  almost 
unweathered,  having  been  recently  washed  out  of  deep  gullies. 

Because  of  the  porous  character  of  the  soil  and  subsoil,  and  the  conse- 
quent deep-feeding  range  afforded  to  plant  roots,  and  also  because  of  the 
liability  to  overflow,  it  is  very  doubtful  if  any  purchased  materials  should 
be  applied  to  this  kind  of  land;  but  legumes  should  be  grown  in  rotation 
where  conditions  permit. 


River  Sand  (1380) 

This  type  covers  about  130  acres  along  the  Ohio  river  in  the  southward 
extension  southwest  of  Rosiclare  and  is  a deposit  formed  by  water  and  re- 
worked to  some  extent  by  wind.  The  sand  is  largely  derived  from  a sand 
bar  beside  this  area  on  the  north  side  of  the  river,  this  sand  bar  being  ex- 
posed. during  low  water. 

There  is  very  little  difference  between  the  different  strata  of  sand  ex- 
cept tkat  occasional  layers  of  silt  or  clay  from  2 to  4 inches  thick  are  found 
in  the  subsoil.  These  have  been  deposited  during  overflow  from  the  Ohio 
river. 

The  sand  is  exceedingly  poor  in  organic  matter  and  nitrogen,  altho  the 
ratio  between  the  organic  carbon  and  nitrogen  indicates  that  the  small 
amount  of  organic  matter  present  is  in  moderately  fresh  condition,  as  might 
be  expected  from  the  formation  and  age  of  this  river  sand.  Where  it  is 
cultivated,  legume  crops  should  be  grown  in  the  rotation  if  practicable. 
Considering  its  composition  and  very  porous  character,  no  applications  can 
be  advised  except  nitrogenous  organic  matter,  best  secured  as  a rule  by  le- 
gume crops. 


1912] 


Hardin  County 


21 


(c)  Terrace  Soils 
Gray  Clay  (1516) 

This  type  comprises  about  196  acres,  mostly  in  the  northeast  part  of  the 
county.  There  are  two  small  areas  in  the  southwestern  part  along  small 
streams.  This  with  the  type  described  below  (gray  silt  loam  on  tight 
clay)  represents  an  old  fill,  or  terrace  deposit,  caused  by  the  silting  up  of  the 
Ohio  and  its  tributaries  and  later  cutting  down  thru  them  by  stream  erosion 
to  the  level  of  the  present  bottom  land.  The  topography  is  flat,  with  the 
exception  of  a few  small  draws  that  have  been  made  by  streams. 

The  surface,  o to  6 2/z  inches,  is  a gray  to  dark  drab  clay,  with  iron  stains, 
very  plastic,  and  possessing  the  property  of  shrinkage  to  a marked  degree. 
This  stratum  contains  about  3 percent  of  organic  matter. 

The  subsurface  and  subsoil  are  composed  of  a gray*  sticky,  plastic  clay 
with  blotches  of  yellow. 

The  soil  is  very  difficult  to  work;  it  is  easily  puddled  when  too  wet,  and 
when  dry  is  very  cloddy.  It  granulates  under  proper  conditions  of  moisture. 
Its  chief  value  is  for  permanent  pasture  or  hay,  but  even  for  these  purposes 
it  is  not  a good  soil;  and  because  of  the  physical  difficulties  it  is  doubtful 
if  any  method  of  enrichment  would  be  profitable;  but  if  so  it  would  be  with 
limestone,  organic  matter  and  possibly  phosphorus. 

Gray  Silt  Loam  on  Tight  Clay  (1530) 

This  type  is  like  the  gray  clay  (1516)  in  that  it  is  part  of  an  old  clay  ter- 
race, but  in  this  case  a deposit  of  silt  from  7 to  12  inches  deep  was  made 
upon  the  tight  clay  layer.  It  occurs  in  the  northeastern  part  of  the  county 
along  Harris  creek  and  Saline  river  and  along  three  small  creeks  in  the  vi- 
cinity of  Elizabethtown. 

The  total  area  is  755  acres.  It  is  very  flat  and  poorly  drained.  While 
it  is  a distinct  terrace  yet  part  of  it  overflows  during  extremely  high  water. 
Tile  would  be  of  little  use  because  of  the  almost  impervious  subsoil. 

The  surface  soil,  o to  62/$  inches,  is  a gray  silt  loam  having  about 
2 percent  of  organic  matter,  sometimes  with  a yellow  tinge  due  to  iron.. 
It  varies  from  a loose  pulverulent  silt  loam  to  a somewhat  sticky  clayey 
silt  loam. 

The  subsurface  stratum  is  sometimes  represented  by  a layer  of  gray  silt 
loam  extending  to  a depth  of  12  inches,  but  often  the  clay  subsoil  begins 
at  a depth  of  7 inches  and  continues  without  any  material  change  to  a 
depth  of  40  inches.  The  subsoil  is  a gray  or  yellowish  clay,  tough,  plastic 
and  nearly  impervious. 

The  type  has  a very  low  value  for  agricultural  purposes.  It  produces  but 
little  corn  or  wheat,  and  grass  makes  but  poor  growth.  Much  of  it  is  still 
covered  with  timber,  and  probably  this  is  the  best  crop  that  can  be  grown 
upon  it.  If  put  under  cultivation  and  protected  from  overflow,  it  should  be 
treated  with  ground  limestone,  and  legume  crops  should  be  grown  in  the 
rotation ; and  with  long  continued  cropping  phosphorus  would  need  to  be 
supplied,  altho  in  its  virgin  condition  it  is  fairly  rich  in  that  element,  as 
shown  in  Table  2. 


22 


Soil  Report  No.  3 


[August, 


APPENDIX 

A study  of  the  soil  map  and  the  tabular  statements  concerning  crop  re- 
quirements, the  plant  food  content  of  the  different  soil  types,  and  the  actual 
results  secured  from  definite  field  trials  with  different  methods  or  systems 
of  soil  improvement,  and  a careful  study  of  the  discussion  of  general  prin- 
ciples and  of  the  descriptions  of  individual  soil  types  will  furnish  the  most 
necessary  and  useful  information  for  the  practical  improvement  and  perma- 
nent preservation  of  the  productive  power  of  every  kind  of  soil  on  every 
farm  in  the  county. 

More  complete  information  concerning  the  most  extensive  and  import- 
ant soil  types  in  the  great  soil  areas  in  all  parts  of  Illinois  is  contained  in 
Bulletin  123,  “The  Fertility  of  Illinois  Soils,”  which  contains  a colored  gen- 
eral survey  soil  map  of  the  entire  state. 

Other  publications  of  general  interest  are: 

Bulletin  No.  76,  “Alfalfa  on  Illinois  Soils” 

Bulletin  No.  94,  “Nitrogen  Bacteria  and  Legumes” 

Bulletin  No.  99,  “Soil  Treatment  for  the  Lower  Illinois  Glaciation” 

Bulletin  No.  115,  “Soil  Improvement  for  the  Worn  Hilk  Lands  of  Illinois” 

Bulletin  No.  125,  “Thirty  Years  of  Crop  Rotation  on  the  Common  Prairie  Lands  of 
Illinois” 

Circular  No.  no,  “Ground  Limestone  for  Acid  Soils” 

Circular  No.  127,  “Shall  we  use  Natural  Rock  Phosphate  or  Manufactured  Acid  Phos- 
phate for  the  Permanent  Improvement  of  Illinois  Soils?” 

Circular  No.  129,  “The  Use  of  Commercial  Fertilizers” 

Circular  No.  149,  “Some  Results  of  Scientific  Soil  Treatment”  and  “Methods  and  Re- 
sults of  Ten  Years’  Soil  Investigation  in  Illinois” 

■NOTE. — Information  as  to  where  to  obtain  limestone,  phosphate,  bone  meal,  and  po- 
tassium salts,  methods  of  application,  etc.,  will  also  be  found  in  Circulars  no  and  149. 

Soil  Survey  Methods 

The  detail  soil  survey  of  a county  consists  essentially  of  indicating  on 
a map  the  location  and  extent  of  the  different  soil  types;  and,  since  the 
value  of  the  survey  depends  upon  its  accuracy,  every  reasonable  means  is 
employed  to  make  it  trustworthy.  To  accomplish  this  object  three  things 
are  essential : first,  careful,  well-trained  men  to  do  the  work ; second,  an  ac- 
curate base  map  upon  which  to  show  the  results  of  their  work:  and,  third, 
the  means  necessary  to  enable  the  men  to  place  the  soil-type  boundaries, 
streams,  etc.,  accurately  upon  the  map. 

The  men  selected  for  the  work  must  be  able  to  keep  their  location 
exactly  and  to  recognize  the  different  soil  types,  with  their  principal  varia- 
tions and  limits,  and  they  must  show  these  upon  the  maps  correctly.  A 
definite  system  is  employed  in  checking  up  this  work.  As  an  illustration,  one 
soil  expert  will  survey  and  map  a strip  80  rods  or  160  rods  wide  and  any 
convenient  length,  while  his  associate  will  work  independently  on  another 
strip  adjoining  this  area,  and,  if  the  work  is  correctly  done,  the  soil  type 
boundaries  will  match  up  on  the  line  between  the  two  strips. 

An  accurate  base  map  for  field  use  is  absolutely  necessary  for  soil  map- 
ping. The  base  maps  are  made  on  a scale  of  one  inch  to  the  mile.  The 
official  data  of  the  original  or  subsequent  land  survey  are  used  as  a basis  in 
the  construction  of  these  maps,  while  the  most  trustworthy  county  map  avail- 
able is  used  in  locating  temporarily  the  streams,  roads,  and  railroads.  Since 
the  best  of  these  published  maps  have  seme  inaccuracies,  the  location  of  every 
road,  stream,  and  railroad  must  be  verified  by  the  soil  surveyors,  and  cor- 


Hardin  County 


23 


1912] 


rected  if  wrongly  located.  In  order  to  make  these  verifications  and  correc- 
tions, each  survey  party  is  provided  with  an  odometer  for  measuring  dis- 
tances, and  a plane  table  for  determining  the  directions  of  roads,  railroads, 
etc. 

Each  surveyor  is  provided  with  a base  map  of  the  proper  scale,  which  is 
carried  with  him  in  the  field ; and  the  soil-type  boundaries,  additional  streams, 
and  necessary  corrections  are  placed  with  proper  locations  upon  the  map 
while  the  mapper  is  on  the  area.  Each  section,  or  square  mile,  is  divided  into 
40-acre  plots  on  the  map  and  the  surveyor  must  inspect  every  ten  acres  and 
determine  the  type  or  types  of  soil  composing  it.  The  different  types  are 
indicated  on  the  map  by  different  colors,  pencils  being  carried  in  the  field 
for  this  purpose. 

A small  augur  40  inches  long  forms  for  each  man  an  invaluable  tool  with 
which  he  can  quickly  secure  samples  of  the  different  strata  for  inspection. 
An  extension  for  making  the  augur  80  inches  long  is  taken  by  each  party, 
so  that  any  peculiarity  of  the  deeper  subsoil  layers  may  be  studied.  Each 
man  carries  a compass  to  aid  in  keeping  directions.  Distances  along  roads 
are  measured  by  an  odometer  attached  to  the  axle  of  the  vehicle,  while  dis- 
tances in  the  field  off  the  roads  are  determined  by  pacing,  an  art  in  which 
the  men  become  expert  by  practice.  The  soil  boundaries  can  thus  be  located 
with,  as  high  a degree  of  accuracy  as  can  be  indicated  by  pencil  on  the 
scale  of  one  inch  to  the  mile. 


The  unit  in  the  soil  survey  is  the  soil  type,  and  each  type  possesses  more 
or  less  definite  characteristics.  The  line  of  separation  between  adjoining 
types  is  usually  distinct,  but  sometimes  one  type  will  grade  into  another  so 
gradually  that  it  is  very  difficult  to  draw  the  line  between  them.  In  such 
exceptional  cases,  some  slight  variation  in  the  location  of  soil-type  boundaries 
is  unavoidable. 

Several  factors  must  be  taken  into  account  in  establishing  soil  types. 
These  are  (1)  the  geological  origin  of  the  soil,  whether  residual,  glacial, 
loessial,  alluvial,  colluvial,  or  cumulose;  (2)  the  topography,  or  lay  of  the 
land;  (3)  native  vegetation,  as  forest  or  prairie  grasses;  (4)  the  structure, 
or  the  depth  and  character  of  the  surface,  subsurface,  and  subsoil;  (5)  the 
physical  or  mechanical  composition  of  the  different  strata  composing  the  soil, 
as  the  percentages  of  gravel,  sand,  silt,  clay,  and  organic  matter  which  they 
contain;  (6)  the  texture,  or  porosity,  granulation,  friability,  plasticity,  etc.; 
(7)  the  color  of  the  strata;  (8)  the  natural  drainage;  (9)  agricultural 
value,  based  upon  its  natural  productiveness;  (10)  the  ultimate  chemical 
composition  and  reaction. 

The  common  soil  constituents  are  indicated  in  the  following  outline : 


Soil,  Characteristics 


Organic 

Matter 


Constituents  of  Soils 

f Comprising  undecomposed  and  partially  decayed 
1 vegetable  material 


{' 


Soil 

Constituents 


Inorganic 

Matter 


.001  mm.  to  .03  mm. 
. .03  mm.  to  1.  mm. 
. . . 1.  mm.  to  32  mm. 
. . . 32.  mm.  and  over 


.001  mm*  and  less 


*25  millimeters  equal  1 inch. 

Further  discussion  of  these  constituents  is  given  in  Circular  82. 


24 


Soil  Report  No.  3 


[August, 


Groups  of  Soil  Types 

The  following  gives  the  different  general  groups  of  soils: 

Peats — Consisting  of  35  percent  or  more  of  organic  matter,  sometimes 
mixed  with  more  or  less  sand  or  silt. 

Peaty  loams — 15  to  35  percent  of  organic  matter  mixed  with  much  sand 
and  silt  and  a little  clay. 

Mucks — 15  to  35  percent  of  partly  decomposed  organic  matter  mixed 
with  much  clay  and  some  silt. 

Clays — Soils  with  more  than  25  percent  of  clay,  usually  mixed  with  much 

silt. 

Clay  loams — Soils  with  from  15  to  25  percent  of  clay,  usually  mixed 
with  much  silt  and  some  sand. 

Silt  loams — Soils  with  more  than  50  percent  of  silt  and  less  than  15 
percent  of  clay,  mixed  with  some  sand.  . 

Loams — Soils  with  from  30  to  50  percent  of  sand  mixed  with  much  silt 
and  a little  clay. 

Sandy  loams — Soils  with  from  50  to  75  percent  of  sand. 

Fine  sandy  loams — Soils  with  from  50  to  75  percent  of  fine  sand  mixed 
with  much  silt  and  little  clay. 

Sands — Soils  with  more  than  75  percent  of  sand. 

Gravelly  loams — Soils  with  15  to  50  percent  gravel  with  much  sand  and 
some  sift. 

Gravels — Soils  with  more  than  50  percent  of  gravel. 

Stony  loams — Soils  containing  a considerable  number  of  stones  over  one 
inch  in  diameter. 

Rock  outcrop — Usually  ledges  of  rock  having  no  agricultural  value. 

More  or  less  organic  matter  is  found  in  nearly  all  of  the  above  classes. 

Supply  and  Liberation  of  Plant  Food 

The  productive  capacity  of  land  in  humid  sections  depends  almost  wholly 
upon  the  power  of  the  soil  to  feed  the  crop;  and  this,  in  turn,  depends  both 
upon  the  stock  of  plant  food  contained  in  the  soil  and  upon  the  rate  at  which 
this  is  liberated,  or  rendered  soluble  and  available  for  use  in  plant  growth. 
Protection  from  weeds,  insects,  and  fungous  diseases,  tho  exceedingly  im- 
portant, is  not  a positive  but  a negative  factor  in  crop  production. 

The  chemical  analysis  of  the  soil  gives  the  invoice  of  fertility  actually 
present  in  the  soil  strata  sampled  and  analyzed,  but  the  rate  of  liberation  is 
governed  by  many  factors,  some  of  which  may  be  controlled  by  the  farmer, 
while  others  are  largely  beyond  his  control.  Chief  among  the  important 
controllable  factors  which  influence  the  liberation  of  plant  food  are  lime- 
stone and  decaying  organic  matter,  which  may  be  added  to  the  soil  by  direct 
application  of  ground  limestone  and  farm  manure.  Organic  matter  may  also 
be  supplied  by  green-manure  crops  and  crop  residues,  such  as  clover,  cow- 
peas,  straw,  and  cornstalks.  The  rate  of  decay  of  organic  matter  depends 
largely  upon  its  age  and  origin,  and  it  may  be  hastened  by  tillage.  The 
chemical  analysis  shows  correctly  the  total  organic  carbon,  which  represents, 
as  a rule,  but  little  more  than  half  the  organic  matter;  so  that  20,000 
pounds  of  organic  carbon  in  the  plowed  soil  of  an  acre  correspond  to  nearly 
20  tons  of  organic  matter.  But  this  organic  matter  consists  largely  of  the 


J912] 


Hardin  County 


25 


old  organic  residues  that  have  accumulated  during  the  past  centuries  because 
they  were  resistant  to  decay,  and  2 tons  of  clover  or  cowpeas  plowed  under 
may  have  greater  power  to  liberate  plant  food  than  the  20  tons  of  old  inactive 
organic  matter.  The  recent  history  of  the  individual  farm  or  field  must  be 
depended  upon  for  information  concerning  recent  additions  of  active  organic 
matter,  whether  in  applications  of  farm  manure,  in  legume  crops,  or  in  grass- 
root  sods  of  old  pastures. 

Probably  no  agricultural  fact  is  more  generally  known  by  farmers  and 
landowners  than  that  soils  differ  in  productive  power.  Even  tho  plowed 
alike  and  at  the  same  time,  prepared  the  same  way,  planted  the  same  day 
with  the  same  kind  of  seed,  and  cultivated  alike,  watered  by  the  same  rains 
and  warmed  by  the  same  sun,  nevertheless  the  best  acre  may  produce  twice 
as  large  a crop  as  the  poorest  acre  on  the  same  farm,  if  not,  indeed,  in  the 
same  field;  and  the  fact  should  be  repeated  and  emphasized  that  with  the 
normal  rainfall  of  Illinois  the  productive  power  of  the  land  depends  primarily 
upon  the  stock  of  plant  food  contained  in  the  soil  and  upon  the  rate  at  which 
it  is  liberated,  just  as  the  success  of  the  merchant  depends  primarily  upon 
his  stock  of  goods  and  the  rapidity  of  sales.  In  both  cases  the  stock  of  any 
commodity  must  be  increased  or  renewed  whenever  the  supply  of  such  com- 
modity becomes  so  depleted  as  to  limit  the  success  of  the  business,  whether 
on  the  farm  or  in  the  store. 

As  the  organic  matter  decays,  certain  decomposition  products  are  formed, 
including  much  carbonic  acid,  some  nitric  acid,  and  various  organic  acids, 
and  these  have  power  to  act  upon  the  soil  and  dissolve  the  essential  mineral 
plant  foods,  thus  furnishing  soluble  phosphates,  nitrates,  and  other  salts  of 
potassium,  magnesium,  calcium,  etc.,  for  the  use  of  the  growing  crop. 

As  already  explained,  fresh  organic. matter  decomposes  much  more  rap- 
idly than  the  old  humus,  which  represents  the  organic*  residues  most  resistant 
to  decay  and  which  consequently  have  accumulated  in  the  soil  during  the 
past  centuries.  The  decay  of  this  old  humus  can  be  hastened  both  by  tillage, 
which  maintains  a porous  condition  and  thus  permits  the  oxygen  of  the  air 
to  enter  the  soil  more  freely  and  to  effect  the  more  rapid  oxidation  of  the 
organic  matter,  and  also  by  incorporating  with  the  old  resistant  residues 
some  fresh  organic  matter,  such  as  farm  manure,  clover  roots,  etc.,  which 
decay  rapidly  and  which  thus  furnish  or  liberate  organic  matter  and  inorganic 
food  for  bacteria,  which,  under  such  favorable  conditions  appear  to  have 
power  to  attack  and  decompose  the  old  humus.  It  is  probably  for  this  reason 
that  peat,  a very  inactive  and  inefficient  fertilizer  when  used  by  itself,  becomes 
much  more  effective  when  incorporated  with  fresh  farm  manure ; so  that, 
when  used  together,  two  tons  of  the  mixture  may  be  worth  as  much  as  two 
tons  of  manure,  but  if  applied  separately,  the  peat  has  little  value.  Bacterial 
action  is  also  promoted  by  the  presence  of  limestone. 

The  condition  of  the  organic  matter  of  the  soil  is  indicated  more  or  less 
definitely  by  the  ratio  of  carbon  to  nitrogen.  As  an  average,  the  fresh 
organic  matter  incorporated  with  soils  contains  about  twenty  times  as  much 
carbon  as  nitrogen,  but  the  carbohydrates  ferment  and  decompose  much  more 
rapidly  than  the  nitrogenous  matter;  and  the  old  resistant  organic  residues, 
such  as  are  found  in  normal  subsoils,  commonly  contain  only  five  or  six  times 
as  much  carbon  as  nitrogen.  Soils  of  normal  physical  composition,  such 
as  loam,  clay  loam,  silt  loam,  and  fine  sandy  loam,  when  in  good  productive 
condition,  contain  about  twelve  to  fourteen  times  as  much  carbon  as  nitrogen 
in  the  surface  soil ; while  in  old  worn  soils  that  are  greatly  in  need  of  fresh 


26 


Soil  Report  No.  3 


[August, 


active  organic  manures,  the  ratio  is  narrower,  sometimes  falling  below  ten  of 
carbon  to  one  of  nitrogen.  (Except  in  newly  made  alluvial  soils,  the  ratio 
is  usually  narrower  in  the  subsurface  and  subsoil  than  in  the  surface  stratum.) 

It  should  be  kept  in  mind  that  crops  are  not  made  out  of  nothing.  They 
are  composed  of  ten  different  elements  of  plant  food,  every  one  of  which  is 
absolutely  essential  for  the  growth  and  formation  of  every  agricultural  plant. 
Of  these  ten  elements  of  plant  food,  only  two  (carbon  and  oxygen)  are 
secured  from  the  air  by  all  agricultural  plants,  only  one  (hydrogen)  from 
water,  and  seven  from  the  soil.  Nitrogen,  one  of  these  seven  elements 
secured  from  the  soil  by  all  plants,  may  also  be  secured  from  the  air  by  one 
class  of  plants  (legumes),  in  case  the  amount  liberated  from  the  soil  is  insuf- 
ficient; but  even  these  plants  (which  include  only  the  clovers,  peas,  beans,  and 
vetches  among  our  common  agricultural  plants)  secure  only  from  the  soil  six 
elements  (phosphorus,  potassium,  magnesium,  calcium,  iron  and  sulfur),  and 
also  utilize  the  soil  nitrogen  so  far  as  it  becomes  soluble  and  available  during 
their  period  of  growth. 

Plants  are  made  of  plant-food  elements  in  just  the  same  sense  that 
a building  is  made  of  wood  and  iron,  brick,  stone,  and  mortar.  Without 
materials,  nothing  material  can  be  made.  The  normal  temperature,  sunshine, 
rainfall,  and  length  of  season  in  central  Illinois  are  sufficient  to  produce 
50  bushels  of  wheat  per  acre,  100  bushels  of  corn,  100  bushels  of  oats,  and 
4 tons  of  clover  hay;  and,  where  the  land  is  properly  drained  and  properly 
tilled,  such  crops  would  frequently  be  secured  if  the  plant  foods  were  present 
in  sufficient  amounts  and  liberated  at  a sufficiently  rapid  rate  to  meet  the  abso- 
lute needs  of  the  crops. 


Crop  Requirements 

The  accompanying  table  shows  the  requirements  of  such  crops  for  the 
five  most  important  plant  food  elements  which  the  soil  must  furnish.  (Iron 
and  sulfur  are  supplied  normally  in  sufficient  abundance  compared  with  the 
amounts  needed  by  plants,  so  that  they  are  not  known  ever  to  limit  the  yield 
of  general  farm  crops  grown  under  normal  conditions). 


Table  A. — Plant  Food  in  Wheat,  Corn,  Oats,  and  Clover 


Produce 

Nitro- 

gen. 

pounds 

Phos- 

phorus, 

pounds 

Potas- 

sium, 

pounds 

Magne- 

sium, 

pounds 

Cal- 

cium, 

pounds 

Kind 

Amount 

Wheat,  grain 

SO  bu. 

71 

12 

13 

4 

1 

Wheat  straw 

2 y2  tons 

25 

4 

45 

4 

10 

Corn,  g^ain  

100  bu. 

100 

17 

19 

7 

1 

Corn  stover 

3 tons 

48 

6 

52 

10 

21 

Corn  cobs  

l/2  ton 

2 

2 

Oats,  grain  

100  bu. 

66 

11 

16 

4 

2 

Oat  straw 

2l/2  tons 

31 

5 

52 

7 

15 

Clover  seed  

4 bu 

7 

2 

3 

1 

1 

Clover  hay  . 

4 tons 

160 

20 

120 

31 

117 

Total  in  grain  and  seed 

244* 

42 

51 

16 

4 

Total  in  four  crops 

510* 

77 

322 

68 

168 

*Tbe->e  amounts  include  the  nitrogen  contained  in  the  clover  seed  or  hay,  which 
however  may  be  secured  from  the  air. 


Hardin  County 


27 


1912 ] 

To  be  sure,  these  are  large  yields,  but  shall  we  try  to  make  possible  the 
production  of  yields  only  half  or  a quarter  as  large  as  these,  or  shall  we 
set  as  our  ideal  this  higher  mark,  and  then  approach  is  as  nearly  as  possible 
with  profit?  Among  the  four  crops,  corn  is  the  largest,  with  a total  yield 
of  more  than  six  tons  per  acre;  and  yet  the  ioo-bushel  crop  of  corn  is  often 
produced  on  rich  pieces  of  land  in  good  seasons.  In  very  practical  and 
profitable  systems  of  farming,  the  Illinois  Experiment  Station  has  produced, 
as  an  average  of  the  six  years  1905  to  1910,  a yield  of  87  bushels  of  corn 
per  acre  in  grain  farming  (with  limestone  and  phosphorus  applied,  and  with 
crop  residues  and  legume  crops  turned  under),  and  90  bushels  per  acre  in 
live-stock  farming  (with  limestone,  phosphorus,  and  manure). 

On  the  Fairfield  experiment  field  in  Wayne  county,  on  the  common 
prairie  land  of  southern  Illinois,  yields  have  been  obtained  in  favorable  sea- 
sons as  high  as  90  bushels  per  acre  of  corn,  and  3^2  tons  of  air-dry  clover 
hay. 

The  importance  of  maintaining  a rich  surface  soil  cannot  be  too  strongly 
emphasized.  It  is  well  illustrated  by  data  from  the  Rothamsted  Experiment 
Station,  the  oldest  in  the  world.  Thus  on  Broadbalk  field,  where  wheat  has 
been  grown  since  1844,  the  average  yields  for  the  ten  years  1892  to  1901 
were  12.3  bushels  per  acre  on  Plot  3 (unfertilized)  and  31.8  bushels  on 
Plot  7 (well  fertilized),  but  the  amounts  of  both  nitrogen  and  phosphorus 
in  the  subsoil  (9  to  27  inches)  were  distinctly  greater  in  Plot  3 than  in 
Plot  7,  thus  showing  that  the  higher  yields  from  Plot  7 were  due  to  the 
fact  that  the  plowed  soil  had  been  enriched.  In  1893  Plot  7 contained  per 
acre  in  the  surface  soil  (o  to  9 inches)  about  600  pounds  more  nitrogen  and 
900  pounds  more  phosphorus  than  Plot  3.  Even  a rich  subsoil  has  little 
value  if  it  lies  beneath  a worn-out  surface. 

Methods  oe  Liberating  Plant.  Food 

Limestone  and  decaying  organic  matter  are  the  principal  materials  the 
farmer  can  utilize  most  profitably  to  bring  about  the  liberation  of  plant  food. 

The  limestone  corrects  the  acidity  of  the  soil  and  thus  encourages  the 
development  not  only  of  the  nitrogen-gathering  bacteria  which  live  in  the 
nodules  on  the  roots  of  clover,  cowpeas,  and  other  legumes,  but  also  the 
nitrifying  bacteria  which  have  power  to  transform  the  insoluble  and  unavail- 
able organic  nitrogen  into  soluble  and  available  nitrate  nitrogen. 

At  the  same  time  the  products  of  this  decomposition  have  power  to  dis- 
solve the  minerals  contained  in  the  soil,  such  as  potassium  and  magnesium, 
and  also  to  dissolve  the  insoluble  phosphate  and  limestone  which  may  be 
applied  in  low-priced  forms. 

Tillage,  or  cultivation,  also  hastens  the  liberation  of  plant  food  by  permit- 
ting the  air  to  enter  the  soil  and  burn  out  the  organic  matter;  but  it  should 
never  be  forgotten  that  tillage  is  wholly  destructive,  that  it  adds  nothing 
whatever  to  the  soil,  but  always  leaves  the  soil  poorer.  Tillage  should  be 
practiced  so  far  as  is  necessary  to  prepare  a suitable  seed-bed  for  root  devel- 
opment and  also  for  the  purpose  of  killing  weeds,  but  more  than  this  is 
unnecessary  and  unprofitable  in  seasons  of  normal  rainfall ; and  it  is  much 
better  actually  to  enrich  the  soil  by  proper  applications  or  additions,  including 
limestone  and  organic  matter  (both  of  which  have  power  to  improve  the 
physical  condition  as  well  as  to  liberate  plant  food)  than  merely  to  hasten 
soil  depletion  by  means  of  excessive  cultivation. 


28 


Soil  Report  No.  3 


[August, 


Permanent  Soil  Improvement 

The  best  and  most  profitable  methods  for  the  permanent  improvement  of 
the  common  soils  of  Illinois  are  as  follows : 

(1)  If  the  soil  is  acid  apply  at  least  two  tons  per  acre  of  ground  lime- 
stone, preferably  at  times  magnesian  limestone  (CaC03MgC03),  which 
contains  both  calcium  and  magnesium,  and  has  slightly  greater  power  to  cor- 
rect soil  acidity,  ton  for  ton,  than  the  ordinary  calcium  limestone  (CaC03)  ; 
and  continue  to  apply  about  two  tons  per  acre  of  ground  limestone  every  four 
or  five  years.  On  strongly  acid  soils,  or  in  preparing  the  land  for  alfalfa,  five 
tons  per  acre  of  ground  limestone  may  well  be  used  for  the  first  application. 

(2)  Adopt  a good  rotation  of  crops,  including  a liberal  use  of  legumes, 
and  increase  the  organic  matter  of  the  soil  either  by  plowing  under  the 
legume  crops  and  other  crop  residues  (straw  and  corn  stalks)  or  by  using 
for  feed  and  bedding  practically  all  of  the  crops  raised  and  returning  the 
manure  to  the  land  with  the  least  possible  loss.  No  one  can  say  in  advance 
what  will  prove  to  be  the  best  rotation  of  crops,  because  of  variation  in 
farms  and  farmers,  and  in  prices  for  produce,  but  the  following  are  suggested 
to  serve  as  models  or  outlines : 

First  year,  corn  (with  some  winter  legume,  such  as  red  clover,  alsike,  sweet  clover, 
or  alfalfa,  or  a mixture,  seeded  on  part  of  the  field  at  the  last  cultivation). 

Second  year,  oats  or  barley  or  wheat  (fall  or  spring)  on  one  part  and  cowpeas  or 
soybeans  where  the  winter  catch  crop  is  plowed  'down  late  in  the  spring. 

Third  year,  wheat  or  oats  (with  clover  or  clover  and  grass). 

Fourth  year,  clover  or  clover  and  grass. 

Fifth  year,  wheat  and  clover  or  grass  and  clover. 

Sixth  year,  clover  or  clover  and  grass. 

Of  course  there  should  be  as  many  fields  as  there  are  years  in  the  rota- 
tion. In  grain  farming,  with  wheat  grown  the  third  and  fifth  years,  most  of 
the  coarse  products  should  be  returned  to  the  soil,  and  the  clover  may  be 
clipped  and  left  on  the  land  (only  the  clover  seed  being  sold  the  fourth  and 
sixth  years)  ; or,  in  live-stock  farming,  the  field  may  be  used  three  years  for 
timothy  and  clover  pasture  and  meadow  if  desired.  The  system  may  be 
reduced  to  a five-year  rotation  by  cutting  out  either  the  second  or  the  sixth 
year;  and  to  a four-year  system  by  omitting  the  fifth  and  sixth  years. 

With  two  years  of  corn,  followed  by  oats  with  clover-seeding  the  third 
year,  and  by  clover  the  fourth  year,  all  produce  can  be  used  for  feed  and 
bedding  if  other  land  is  available  for  permanent  pasture.  Alfalfa  may  be 
grown  on  a fifth  field  for  four  or  eight  years,  which  is  to  be  alternated  with 
one  of  the  four;  or  the  alfalfa  may  be  moved  every  five  years,  and  thus 
rotated  over  all  five  fields  every  twenty-five  years. 

Other  four-year  rotations  more  suitable  for  grain  farming  are : 

Wheat  (and  clover),  corn,  oats,  and  clover,  or  corn  (and  clover),  cowpeas,  wheat, 
and  clover.  (Alfalfa  may  be  grown  on  a fifth  field  and  rotated  every  five  years, 
the  hay  being  sold.) 

Good  three-year  rotations  are : 

Corn,  oats,  dnd  clover;  corn,  wheat,  and  clover;  or  wheat  (and  clover),  corn  (and 
clover),  and  cowpeas,  in  which  two  cover  crops  and  one  regular  crop  of  legumes 
are  grown  in  three  years. 

A five-year  rotation  of  (1)  corn  (and  clover),  (2)  cowpeas,  (3)  wheat, 
(4)  clover,  (5)  wheat  (and  clover),  allows  legumes  to  be  seeded  four  times, 
and  alfalfa  may  be  grown  on  a sixth  field  for  five  or  six  years  in  the  com- 


Hardin  County 


29 


1912] 

bination  rotation,  alternating  between  two  fields  every  five  years,  or  rotating 
over  all  fields  if  moved  every  six  years. 

To  avoid  clover  sickness  it  may  sometimes  be  necessary  to  substitute  red 
clover  or  alsike  for  the  other  in  about  every  third  rotation,  and  at  the  same 
time  to  discontinue  their  use  in  the  cover-crop  mixture.  If  the  corn  crop 
is  not  too  rank,  cowpeas  or  soybeans  may  also  be  used  as  a cover-crop  (seeded 
at  the  last  cultivation)  in  the  southern  part  of  the  state  and,  if  necessary 
to  avoid  disease,  these  may  well  alternate  in  successive  rotations. 

For  easy  figuring  it  may  well  be  kept  in  mind  that  the  following  amounts 
of  nitrogen  are  required  for  the  produce  named : 

1 bushel  of  oats  (grain  and  straw)  requires  1 pound  of  nitrogen. 

1 bushel  of  corn  (grain  and  stalks)  requires  V/2  pounds  of  nitrogen. 

I bushel  of  wheat  (grain  and  straw)  requires  2 pounds  of  nitrogen. 

I ton  of  timothy  requires  24  pounds  of  nitrogen. 

1 ton  of  clover  contains  40  pounds  of  nitrogen. 

1 ton  of  cowpeas  contains  43  pounds  of  nitrogen. 

I ton  of  average  manure  contains  10  pounds  of  nitrogen. 

The  roots  of  clover  contain  about  half  as  much  nitrogen  as  the  tops,  and 
the  roots  of  cowpeas  contain  about  one-tenth  as  much  as  the  tops . 

Soils  of  moderate  productive  power  will  furnish  as  much  nitrogen  to 
clover  (and  two  or  three  times  as  much  to  cowpeas)  as  will  be  left  in  the 
roots  and  stubble.  For  grain  crops,  as  wheat,  corn,  and  oats,  about  two- 
thirds  of  the  nitrogen  is  contained  in  the  grain  and  one-third  in  the  straw 
or  stalks.  ( See  also  discussion  of  “The  Potassium  Problem,”  on  pages  below. ) 

(3)  On  all  lands  deficient  in  phosphorus  (except  on  those  susceptible 
to  serious  erosion  by  surface  washing  or  gullying)  apply  that  element  in 
considerably  larger  amounts  than  are  required  to  meet  the  actual  needs  of 
the  crops  desired  to  be  produced.  The  abundant  information  thus  far  se- 
cured shows  positively  that  fine-ground  natural  rock  phosphate  can  be  used 
successfully  and  very  profitably,  and  clearly  indicates  that  this  material  will 
be  the  most  economical  form  of  phosphorus  to  use  in  all  ordinary  systems 
of  permanent,  profitable  soil  improvement.  The  first  application  may  well 
be  one  ton  per  acre,  and  subsequently  about  one-half  ton  per  acre  every  four 
or  five  years  should  be  applied,  at  least  until  the  phosphorus  content  of  the 
plowed  soil  reaches  2,000  pounds  per  acre,  which  may  require  a total  ap- 
plication of  from  three  to  five  or  six  tons  per  acre  of  raw  phosphate  con- 
taining 12 Yz  percent  of  the  element  phosphorus. 

Steamed  bone  meal  and  even  acid  phosphate  may  be  used  in  emergencies, 
but  it  should  always  be  kept  in  mind  that  phosphorus  delivered  in  Illinois 
costs  about  3 cents  a pound  in  raw  phosphate  (direct  from  the  mine  in  car- 
load lots),  but  10  cents  a pound  in  steamed  bone  meal,  and  about  12  cents 
a pound  in  acid  phosphate,  both  of  which  cost  too  much  per  ton  to  permit 
their  common  purchase  by  farmers  in  carload  lots,  which  is  not  the  case 
with  limestone  or  raw  phosphate. 

Phosphorus  once  applied  to  the  soil  remains  in  it  until  removed  in  crops, 
unless  carried  away  mechanically  by  soil  erosion.  (The  loss  by  leaching 
is  only  about  pounds  per  acre  per  annum,  so  that  more  than  150  years 
would  be  required  to  leach  away  the  phosphorus  applied  in  one  ton  of  raw 
phosphate.) 

The  phosphate  and  limestone  may  be  applied  at  any  time  during  the 
rotation,  but  a good  methpd  is  to  apply  the  limestone  after  plowing  and 
work  it  into  the  surface  soil  in  preparing  the  seed  bed  for  wheat,  oats,  rye, 


30 


Soil  Report  No.  3 


[August, 


or  barley,  where  clover  is  to  be  seeded ; while  phosphate  is  best  plowed  under 
with  farm  manure,  clover,  or  other  green  manures,  which  serve  to  liberate 
the  phosphorus. 

(4)  Until  the  supply  of  decaying  organic  matter  has  been  made  ade- 
quate, on  the  poorer  types  of  upland  timber  and  gray  prairie  soils  some 
temporary  benefit  may  be  derived  from  the  use  of  a soluble  salt  or  mixture 
of  salts,  such  as  kainit,  which  contains  both  potassium  and  magnesium  in 
soluble  form  and  also  some  common  salt  (sodium  chlorid)  . About  600 
pounds  per  acre  of  kainit  applied  and  turned  under  with  the  raw  phosphate 
will  help  to  dissolve  the  phosphorus  as  well  as  to  furnish  available  potas- 
sium and  magnesium,  and  for  a few  years  such  use  of  kainit  will  no  doubt 
be  profitable  on  lands  deficient  in  organic  matter,  but  the  evidence  thus  far 
secured  indicates  that  its  use  is  not  absolutely  necessary  and  that  it  will  not 
be  profitable  after  adequate  provision  is  made  for  decaying  organic  matter, 
since  this  will  necessitate  returning  to  the  soil  either  all  produce  except  the 
grain  (in  grain  farming)  or  the  manure  produced  in  live-stock  farming. 
(Where  hay  or  straw  are  sold,  manure  should  be  bought.) 

On  soils  which  are  subject  to  surface  washings,  including  especially  the 
yellow  silt  loam  of  the  upland  timber  area,  and  to  some  extent  the  yellow- 
gray  silt  loam,  and  other  more  rolling  areas,  the  supply  of  minerals  in  the 
subsurface  and  subsoil  (which  gradually  renew  the  surface  soil)  tend  to 
provide  for  a low-grade  system  of  permanent  agriculture  if  some  use  is  made 
of  legume  plants,  as  in  long  rotations  with  much  pasture,  because  both  the 
minerals  and  nitrogen  are  thus  provided  in  some  amount  almost  permanently ; 
but  where  such  lands  are  farmed  under  such  a system  not  more  than  two  or 
three  grain  crops  shoud  be  grown  during  a period  of  ten  or  twelve  years, 
the  land  being  kept  in  pasture  most  of  the  time ; and  where  the  soil  is  acid  a 
liberal  use  of  limestone,  as  top  dressings  if  necessary,  and  occasional  re- 
seeding with  clovers  will  benefit  both  the  pasture  and  indirectly  the  grain 
crops. 

Advantage  of  Crop  Rotation  and  Permanent  Systems 

It  should  be  noted  that  clover  is  not  likely  to  be  well  infected  with  the 
clover  bacteria  during  the  first  rotation  on  a given  farm  or  field  where  it 
has  not  been  grown  before  within  recent  years;  but  even  a partial  stand  of 
clover  the  first  time  will  probably  provide  a thousand  times  as  many  bac- 
teria for  the  next  clover  crop  as  one  could  afford  to  apply  in  artificial  inocu- 
lation, for  a single  root-tubercle  may  contain  a niillion  bacteria  developed 
from  one  during  the  season’s  growth. 

This  is  only  one  of  several  advantages  of  the  second  course  of  the  rota- 
tion over  the  first  course.  Thus  the  mere  practice  of  crop  rotation  is  an  ad- 
vantage, especially  in  helping  to  rid  the  land  of  insects  and  foul  grass  and 
weeds.  ' The  deep-rooting  clover  crop  is  an  advantage  to  subsequent  crops 
because  of  that  characteristic.  The  larger  applications  of  organic  manures 
(made  possible  by  the  larger  crops)  are  a great  advantage;  and  in  systems 
of  permanent  soil  improvement,  such  as  are  here  advised  and  illustrated, 
more  limestone  and  more  phosphorus  are  provided  than  are  needed  for  the 
meager  or  moderate  crops  produced  during  the  first  rotation,  and  conse- 
quently the  crops  in  the  second  rotation  have  the  advantage  of  such  accumu- 
lated residues  (well  incorporated  with  the  plowed  soil)  in  addition  to  the 
regular  applications  made  during  the  second  rotation. 


Hardin  County 


31 


I<y^\ 


This  means  that  these  systems  tend  positively  toward  the  making-  of 
richer  lands.  The  ultimate  analyses  recorded  in  the  tables  give  the  absolute 
invoice  of  these  Illinois  soils.  They  show  that  most  of  them  are  positively 
deficient  only  in  limestone,  phosphorus,  and  nitrogenous  organic  matter;  and 
the  accumulated  information  from  careful  and  long-continued  investigations 
in  different  parts  of  the  United  States  clearly  establish  the  fact  that  in  gen- 
eral farming  these  essentials  can  be  supplied  with  greatest  economy  and 
profit  by  the  use  of  ground  natural  limestone,  very  finely  ground  natural 
rock  phosphate,  and  legume  crops  to  be  plowed  under  directly  or  in  farm 
manure.  On  normal  soils  no  other  applications  are  absolutely  necessary, 
but,  as  already  explained,  the  addition  of  some  soluble  salt  in  the  beginning 
of  a system  of  improvement  on  some  of  these  soils  produces  temporary 
benefit,  and  if  some  inexpensive  salt,  such  as  kainit,  is  used,  it  may  produce 
sufficient  increase  to  more  than  pay  the  added  cost. 

The  Potassium  Problem 

As  reported  in  Illinois  Bulletin  123,  where  wheat  has  been  grown  every 
year  for  more  than  half  a century  at  Rothamsted,  England,  exactly  the  same 
increase  was  produced  (5.6  bushels  per  acre),  as  an  average  of  the  first 
24  years,  whether  potassium,  magnesium,  or  sodium  was  applied,  the  rate  of 
application  per  annum  being  200  pounds  of  potassium  sulfate  and  molecular 
equivalents  of  magnesium  sulfate  and  sodium  sulfate.  As  an  average  of 
60  years  (1852  to  1911)  the  yield  of  wheat  has  been  12.7  bushels  on  un- 
treated land,  23.3  bushels  where  86  pounds  of  nitrogen  and  29  pounds  of 
phosphorus  per  acre  per  annum  were  applied ; and,  as  further  additions,  85 
pounds  of  potassium  raised  the  yield  to  31.3  bushels;  52  pounds  of  mag- 
nesium raised  it  to  29.2  bushels;  and  50  pounds  of  sodium  raised  it  to 
29.5  bushels.  Where  potassium  was  applied  the  average  wheat  crop  re- 
moved 40  pounds  of  that  element  in  the  grain  and  straw,  or  three  times  as 
much  as  would  be  removed  in  the  grain  only  for  such  crops  as  are  suggested 
in  Table  A.  The  Rothamsted  soil  contained  an  abundance  of  limestone,  but  no 
organic  matter  was  provided  except  the  little  in  the  stubble  and  roots  of  the 
wheat  plants. 

On  another  field  at  Rothamsted  the  average  yield  of  barley  for  60  years 
(1852  to  1911)  has  been  14.2  bushels  on  untreated  land,  38.1  bushels  where 
43  pounds  of  nitrogen  and  29  pounds  of  phosphorus  have  been  applied 
per  acre  per  annum ; while  the  further  addition  of  85  pounds  of  potassium, 
19  pounds  of  magnesium,  and  14  pounds  of  sodium  (all  in  sulfates)  raised 
the  average  yield  to  41.5  bushels,  but,  where  only  70  pounds  of  sodium  were 
applied  in  addition  to  the  nitrogen  and  phosphorus,  the  average  has  been 
43.0  bushels.  Thus,  as  an  average  of  60  years,  the  use  of  sodium  pro- 
duced 1.8  bushels  less  wheat  and  1.5  bushels  more  barley  than  the  use  of 
potassium,  with  both  grain  and  straw  removed  and  no  organic  manures 
returned. 

In  recent  years  the  effect  of  potassium  is  becoming  much  more  marked 
than  that  of  sodium  or  magnesium,  on  the  wheat  crop ; but  this  must  be 
expected  to  occur  in  time  where  no  potassium  is  returned  in  straw  or  manure, 
and  no  provision  made  for  liberating  potassium  from  the  supply  still  re- 
maining in  the  soil.  If  more  than  three-fourths  of  the  potassium  removed 
were  returned  in  the  straw  (see  Table  A),  and  if  the  decomposition  prod- 
ucts of  the  straw  have  power  to  liberate  additional  amounts  of  potassium 
from,  the  soil,  the  necessity  of  purchasing  potassium  in  a good  system  of 
farming  on  such,  land  is  very  remote. 


32 


Soil  Report  No.  3 


[August, 


While  about  half  of  the  potassium,  nitrogen,  and  organic  matter,  and 
about  one-fourth  of  the  phosphorus,  contained  in  manure,  will  be  lost  by 
three  or  four  months’  exposure  in  the  ordinary  pile  in  the  barn  yard,  there 
is  practically  no  loss  if  plenty  of  absorbent  bedding  is  used  on  cement  floors, 
and  if  the  manure  is  hauled  to  the  field  and  spread  within  a day  or  two 
after  it  is  produced.  Again,  while  the  animals  destroy  two-thirds  of  the 
organic  matter  and  retain  one-fourth  of  the  nitrogen  and  phosphorus  in 
average  live-stock  farming,  they  retain  less  than  one-tenth  of  the  potassium, 
from  the  food  consumed ; so  that  the  actual  loss  of  potassium  in  the  products 
sold  from  the  farm,  either  in  grain  farming  or  in  live-stock  farming,  is 
wholly  negligible  on  land  containing  25,000  pounds  or  more  of  potassium 
in  the  surface  673  inches. 

The  removal  of  one  inch  of  soil  per  century  by  surface  washing  (which 
is  likely  to  occur  wherever  there  is  satisfactory  surface  drainage  and  frequent 
cultivation)  would  permanently  maintain  the  potassium  in  grain  fanning 
by  renewal  from  the  subsoil,  provided  one-third  of  the  potassium  is  removed 
by  cropping  before  the  soil  is  carried  away. 

From  all  of  these  facts  it  will  be  seen  that  the  potassium  problem  is  not 
one  of  addition  but  of  liberation;  and  the  Rothamsted  records  show  that 
for  many  years  other  soluble  salts  have  practically  the  same  power  as  po- 
tassium to  increase  crop  yields  in  the  absence  of  .sufficient  decaying  organic 
matter.  Whether  this  action  relates  to  supplying  or  liberating  potassium  for 
its  own  sake,  or  to  the  power  of  the  soluble  salt  to  increase  the  availability 
of  phosphorus  or  other  elements,  it  is  not  known,  but  where  much  potassium 
is  removed,  as  in  the  entire  crops  at  Rothamsted,  with  no  return  of  organic 
residues,  probably  the  soluble  salt  functions  in  both  ways. 

As  an  average  of  IT2  separate  tests  conducted  in  1907,  T908,  1909  and 
1910  on  the  Fairfield  experiment  field,  an  application  of  200  pounds  of 
potassium  sulfate,  containing  85  pounds  of  potassium  costing  $5.10,  in- 
creased the  yield  of  corn  by  9.3  bushels  per  acre : while  600  pounds  of  kainit, 
containing  only  60  pounds  of  potassium  and  costing  $4.00,  gave  an  increase 
of  10.7  bushels.  Thus,  at  40  cents  a bushel  for  corn,  the  kainit  has  paid  for 
itself;  but  these  results,  like  those  at  Rothamsted,  were  secured  where  no 
adequate  provision  had  been  made  for  decaying  organic  matter. 

Additional  experiments  at  Fairfield  include  an  equally  complete  test  with 
potassium  sulfate  and  kainit  on  land  to  which  8 tons  per  acre  of  farm 
manure  had  been  applied.  As  an  average  of  112  tests  with  each  material, 
the  200  pounds  of  potassium  sulfate  increased  the  yield  of  corn  by  1.7  bush- 
els, while  the  600  pounds  of  kainit  also  gave  an  increase  of  1.7  bushels. 
Thus,  where  organic  manure  was  supplied,  very  little  effect  was  produced 
by  the  addition  of  either  potassium  sulfate  or  kainit;  in  part  perhaps  because 
the  potassium  removed  in  the  crops  is  mostly  returned  in  the  manure  if 
properly  cared  for;  and  perhaps  in  larger  part  because  the  decaying  organic 
matter  helps  to  liberate  and  bold  in  solution  other  plant  food  elements,  es- 
pecially phosphorus . 

In  laboratory  experiments  at  the  Illinois  Experiment  Station,  it  has  been 
shown  that  potassium  salts  and  most  other  soluble  salts  increase  the  solu- 
bility of  the  phosphorus  in  soil  and  in  rock  phosphate  as  determined  bv  chem- 
ical analysis ; also  that  the  addition  of  glucose  with  rock  phosphate  in  pot- 
culture  experiments  increases  the  availability  of  the  phosphorus,  as  measured 
bv  plant  growth,  altho  the  glucose  consists  only  of  carbon,  hydrogen,  and 
oxygen,  and  thus  contains  no  plant  food  of  value. 


Hardin  County 


33 


1912] 

If  we  remember  that,  as  an  average,  live  stock  destroy  two-thirds  of 
the  organic  matter  of  the  food  consumed,  it  is  easy  to  determine  from  Table 
A that  more  organic  matter  will  be  supplied  in  a proper  grain  system  than 
in  a strictly  live-stock  system;  and  the  evidence  thus  far  secured  from  older 
experiments  at  the  University  and  at  other  places  in  the  state  indicates  that 
if  the  corn  stalks,  straw,  clover,  etc.,  are  incorporated  with  the  soil  as  soon 
as  practicable  after  they  are  produced  (which  can  usually  be  done  in  the 
late  fall  or  early  spring),  there  is  little  or  no  difficulty  in  securing  sufficient 
decomposition  in  our  humid  climate  to  avoid  serious  interference  with  the 
capillary  movement  of  the  soil  moisture,  a common  danger  from  plowing  un- 
der too  much  coarse  manure  of  any  kind  in  the  late  spring  of  a dry  year. 

If,  however,  the  entire  produce  of  the  land  is  sold  from  the  farm,  as 
in  hay  farming,  or  when  both  grain  and  straw  are  sold,  of  course  the  draft 
on  potassium  will  then  be  so  great  that  in  time  it  must  be  renewed  by  some 
sort  of  application.  As  a rule,  such  farmers  ought  to  secure  manure  from 
town,  since  they  furnish  the  bulk  of  the  material  out  of  the  which  manure 
is  produced. 

Calcium  and  Magnesium 

When  measured  by  the  actual  crop  requirements  for  plant  food,  mag- 
nesium and  calcium  are  more  limited  in  some  Illinois  soils  than  potassium. 
But  with  these  elements  we  must  also  consider  the  loss  by  leaching.  As  an 
average  of  90  analyses*  of  Illinois  well-waters  drawn  chiefly  from  glacial 
sands,  gravels,  or  till,  3 million  pounds  of  water  (about  the  average  annual 
drainage  per  acre  for  Illinois)  contained  11  pounds  of  potassium,  130  of 
magnesium,  and  330  of  calcium.  These  figures  are  very  significant,  and  it 
may  be  stated  that  if  the  plowed  soil  is  well  supplied  with  the  carbonates  of 
magnesium  and  calcium,  then  a very  considerable  proportion  of  these 
amounts  will  be  leached  from  that  stratum.  Thus  the  loss  of  calcium  from 
the  plowed  soil  of  an  acre  at  Rothamsted,  England,  where  the  soil  contains 
plenty  of  limestone,  has  averaged  more  than  300  pounds  a year  as  determined 
by  analyzing  the  soil  in  1865  and  again  in  T905.  And  practically  the  same 
amount  of  calcium  was  found  by  analyzing  the  Rothamsted  drainage  waters. 

Common  limestone,  which  is  calcium  carbonate  (CaC03),  contains,  when 
pure,  40  percent  of  calcium,  so  that  800  pounds  of  limestone  are  equivalent 
to  320  po'unds  of  calcium.  Where  10  tons  per  acre  of  ground  limestone  were 
applied  at  Edgewood,  Illinois,  the  average  annual  loss  during  the  next  ten 
years  amounted  to  790  pounds  per  acre.  The  definite  data  from  careful 
investigations  seems  to  be  ample  to  justify  the  conclusion  that  where  lime- 
stone is  needed  at  least  2 tons  per  acre  should  be  applied  every  4 or  5 years. 

It  is  of  interest  to  note  that  thirty  crops  of  clover  of  four  tons  each 
would  require  3,510  pounds  of  calcium,  while  the  most  common  prairie  land 
of  southern  Illinois  contains  only  3,420  pounds  of  total  calcium  in  the 
plowed  soil  of  an  acre.  (See  Soil  Report  No.  t.)  Thus  limestone  has  a 
positive  value  on  some  soils  for  the  plant  food  which  it  supplies,  in  addition 
to  its  value  in  correcting  soil  acidity  and  in  improving  the  physical  condi- 
tion of  the  soil.  Ordinary  limestone  (abundant  in  the  southern  and  western 
parts  of  the  state)  contains  nearly  800  pounds  of  calcium  per  ton;  while  a 
good  grade  of  dolomitic  limestone  (the  more  common  limestone  of  northern 
Illinois)  contains  about  400  pounds  of  calcium  and  300  pounds  of  mag- 
nesium per  ton.  Roth  of  these  elements  are  furnished  in  readily  available 
form  in  ground  dolomitic  limestone. 


*Reported  by  Doctor  Bartow  and  associates,  of  the  Illinois  State  Water  Survey. 


6 3 0.7 

fA  Ls  v 

UNIVERSITY  OF  ILLINOIS 

Agricultural  Experiment  Station 

SOIL  REPORT  NO.  4 

SANGAMON  COUNTY  SOILS 


By  CYRIL,  G.  HOPKINS,  J.  G.  MOSIER, 
J.  H.  PETTIT,  and  J.  E.  READHIMER 


URBANA,  ILLINOIS,  SEPTEMBER,  1912 


State  Advisory  Committee  on  Soil  Investigations 
Ralph  Allen,  Delavan 
F.  I.  Mann,  Gilman 
A.  N.  Abbott,  Morrison 
J.  P.  Mason,  Elgin 

C.  V.  Gregory,  223  W.  Jackson  Blvd.,  Chicago 

Agricultural  Experiment  Station  Staee  on  Soil  Investigations 
Eugene  Davenport,  Director 

Cyril  G.  Hopkins,  Chief  in  Agronomy  and  Chemistry 

Soil  Survey — 

J.  G.  Mosier,  Chief 
A.  F.  Gustafson,  Associate 
S.  V.  Holt,  Associate 
H.  W.  Stewart,  Associate 
H.  C.  Wheeler,  Associate 
F.  A.  Fisher,  Assistant 
F.  M.  Wascher,  Assistant 
R.  W.  Dickenson,  Assistant 
C.  E.  Wheelock,  Assistant 
John  Woodard,  Assistant 

Soil  Analysis — 

J.  H.  Pettit,  Chief 
E.  VanAlstine,  Associate 
J.  P.  Aumer,  Associate 
W.  H.  Sachs,  First  Assistant 
Gertrude  Niederman,  Assistant 
W.  R.  Leighty,  Assistant 
Oran  Keller,  Assistant 
Iv.  F.  Binding,  Assistant 

Soil  Biology — 

A.  E.  Whiting,  First  Assistant 

Soil  Experiment  Fields — 

J.  E.  Readhimer,  Superintendent 
Wm.  G.  Eckhardt,*  Associate 
O.  S.  Fisher,  Associate 
J.  E.  Whitchurch,  Associate 

E.  E.  Hoskins,  Associate 

F.  C.  Bauer,  First  Assistant 
F.  W.  Garrett,  Assistant 

Soils  Extension — 

C.  C.  Logan,  Associate 


*On  leave. 


SANGAMON  COUNTY  SOILS 

By  CYRIL,  G.  HOPKINS,  J.  G.  MOSIER,  J.  H.  PETTIT,  and  J.  E.  READHIMER 


Introduction 

About  two-thirds  of  Illinois  lies  in  the  corn  belt,  where  most  of  the  prairie 
lands  are  black  or  dark  brown  in  color.  In  the  southern  third  of  the  state 
the  prairie  soils  are  largely  of  a gray  color,  and  this  region  is  better  known 
as  the  wheat  belt,  altho  wheat  is  often  grown  in  the  corn  belt  and  corn  is  also 
a common  crop  in  the  wheat  belt. 

Moultrie  county,  representing  the  corn  belt ; Clay  county,  which  is  fairly 
representative  of  the  wheat  belt ; and  Hardin  county,  which  is  taken  to  rep- 
resent the  unglaciated  area  of  the  extreme  southern  part  of  the  state,  were 
selected  for  the  first  Illinois  Soil  Reports  by  counties.  While  these  three 
County  Soil  Reports  were  sent  to  the  Station’s  entire  mailing  list  within  the 
state,  Sangamon  and  other  subsequent  Reports  are  sent  only  to  the  residents 
of  the  county  concerned  and  to  any  one  else  upon  request. 

Each  county  report  is  intended  to  be  as  nearly  complete  in  itself  as  it  is 
practicable  to  make  it,  and,  even  at  the  expense  of  some  repetition,  each  will 
contain  a general  discussion  of  important  fundamental  principles  to  help  the 
farmer  and  landowner  to  understand  the  meaning  of  the  soil  fertility  invoice 
for  the  lands  in  which  he  is  interested.  In  Soil  Report  No.  i,  “Clay  County 
Soils”,  this  discussion  serves  in  part  as  an  introduction,  while  in  this  and 
other  reports  it  will  be  found  in  the  Appendix,  but  if  necessary  it  should  be 
read  and  studied  in  advance  of  the  report  proper. 

Sangamon  county  is  located  in  the  corn  belt  and  almost  \yholly  within  the 
middle  Illinois  glaciation,  the  apparent  exception  being  a small  area  of  about 
two  square  miles  in  the  southern  part,  southeast  of  Auburn,  which  has  soils 
peculiar  to  the  transition  zone  between  the  lower  Illinois  and  middle  Illinois 
glaciations.  This  is  probably  the  northern  terminus  of  that  zone. 

The  general  topography  of  the  county  is  undulating  or  slightly  rolling. 
There  are,  however,  some  very  flat  areas,  and  also  belts  of  very  rolling  or 
hilly  land  along  the  larger  streams,  comprising  about  634  percent  of  the  en- 
tire area  of  the  county.  The  difference  in  topography  is  due  mainly  to  two 
causes,  glacial  action  and  stream  erosion.  Like  most  of  the  state,  this  county 
was  covered  by  a glacial  ice  sheet  during  what  is  known  as  the  Glacial  Period. 
During  this  time  snow  and  ice  accumulated  in  the  vicinity  of  Hudson  Bay  to 
such  an  amount  that  it  flowed  southward  until  a point  was  reached  where  the 
ice  melted  as  rapidly  as  it  advanced. 

In  flowing  across  the  country  the  ice  gathered  up  all  sorts  and  sizes  of 
earthy  material,  including  pebbles,  boulders,  and  even  large  masses  of  rock. 
Many  of  these  were  carried  for  hundreds  of  miles  and  rubbed  against  the 
surface  rocks  or  against  each  other  until  ground  into  powder.  When  the  limit 


1 


2 


Soil  Report  No.  4 


[September, 


of  advance  was  reached,  where  the  ice  largely  melted,  all  of  this  material 
would  accumulate  in  a broad  undulating  ridge  or  moraine.  When  the  ice 
melted  away  more  rapidly  than  the  forward  movement,  the  terminus  of  the 
glacier  would  recede  and  leave  the  moraine  of  boulder  clay  to  mark  the  outer 
limit  of  the  ice  sheet. 

The  ice  made  many  advances,  and  with  each  advance  a terminal  moraine 
was  formed.  This  has  left  a system  of  terminal  moraines  (irregularly 
concentric  with  Lake  Michigan)  haying  generally  a steep  outer  slope  while 
the  inner  slope  is  much  less  and  more  gradual. 

The  material  transported  by  the  glacier  varied  with  the  character  of  the 
rocks  over  which  it  passed.  Granites,  limestones,  sandstones,  shales,  etc., 
were  mixed  and  ground  up  together.  This  mixture  of  all  kinds  of  boulders, 
gravel,  sand,  silt,  and  clay  is  called  boulder  clay,  till,  or  glacial  drift  (or  sim- 
ply drift).  The  grinding  and  denuding  power  of  glaciers  is  enormous.  A 
mass  of  ice  100  feet  thick  exerts  a pressure  of  40  pounds  per  square  inch, 
and  this  ice  sheet  may  have  been  thousands  of  feet  in  thickness. 

The  materials  pushed  along  in  this  mass  of  ice,  especially  the  boulders  and 
pebbles,  became  powerful  agents  for  grinding  and  wearing  away  the  surface 
over  which  the  ice  passed.  Ridges  and  hills  were  rubbed  down  and  valleys 
filled,  and  the  surface  features  changed  entirely.  Occasionally  there  were  hills 
or  ridges  sufficiently  large  or  the  material  composing  them  was  sufficiently 
resistant  to  withstand  the  glacier.  In  such  cases  the  glacier  would  flow  around 
or  over  the  obstacle  if  the  ice  was  thick  enough.  When  the  glacier  melted, 
the  eminence  would  be  left,  in  the  former  case  free  from  drift,  while  in  the 
latter  a thin  mantle  of  drift  would  cover  it.  A preglacial  ridge  in  the  south- 
western part  of  the  county  at  Lowder,  sometimes  taken  as  a glacial  moraine, 
illustrates  the  latter  condition. 

A true  glacial  moraine,  called  the  Buffalo  Hart  moraine,  is  located  in  the 
eastern  part  of  the  county,  extending  northwest  and  southeast.  It  enters  from 
Christian  county  near  Mt.  Auburn,  extends  east  of  Mechanicsburg,  thence  to 
Buffalo,  Buffalo  Hart,  and  on  to  Elkhart  in  Logan  county.  The  average 
width  is  about  two  miles.  It  is  composed  of  a large  number  of  more  or  less 
prominent  knolls,  varying  from  30  to  80  feet  above  the  surrounding  country. 
Among  these  knolls  are  shallow  basins,  giving  the  ridge  a somewhat  peculiar 
“knob-and-basin”  topography.  Near  Buffalo  Hart  this  ridge  was  partly 
forested  and  considerable  erosion  has  occurred,  giving  rise  to  about  three 
square  miles  of  yellow  and  yellow-gray  silt  loam.  (See  also  State  Map  in 
Bulletin  123.) 

A deposit  of  boulder  clay  covers  the  entire  county  to  a depth  of  from  20 
to  80  feet,  with  an  average  of  about  40  feet.  The  surface  left  by  the  glacier 
was  slightly  rolling,  without  very  good  drainage,  but  it  was  later  covered  by 
a deposit  of  loess. 

Physiography 

Sangamon  county  lies  entirely  in  the  drainage  basin  of  the  Sangamon  river. 
The  highest  part  of  the  county  is  toward  the  southwest,  near  Lowder,  on  the 
old  preglacial  ridge  somewhat  more  than  700  feet  above  sea  level.  A cor- 
responding high  point  is  found  in  the  northeast,  on  the  Buffalo  Hart  moraine, 
that  reaches  to  nearly  700  feet.  The  average  altitude  of  the  county  is  near 
585  feet.  The  altitude  of  the  Sangamon  river  where  it  leaves  the  county  is 
512  feet,  while  at  the  east  side  of  the  county  it  is  55°  feet- 


1912] 


Sangamon  County 


3 


The  valley  of  the  Sangamon  river  is  from  50  to  100  feet  below  the  general 
upland.  This  has  permitted  the  small  streams  entering  the  river  to  do  con- 
siderable erosion,  and  as  a result  the  land  adjacent  to  the  bottomland  of  the 
larger  streams  is  cut  up  into  hills  and  valleys  unsuited  for  ordinary  agricul- 
ture. Forests  had  extended  their  way  up  the  streams  and  were  slowly  invad- 
ing the  adjoining  prairies,  before  they  were  put  under  cultivation.  The 
influence  of  the  prevailing  southwesterly  wind  may  be  seen  in  the  greater  ex- 
tension of  the  forests  to  the  north  and  east  of  the  protecting  streams,  as 
shown  in  the  soil  types. 

Soil  Material  and  Soil  Types 

The  Illinois  glacier  covered  Sangamon  county  and  left  a thick  mantle  of 
drift,  completely  burying  the  old  soil  that  preceded  it.  After  this  a long 
period  elapsed  during  which  a deep  soil  was  formed  on  the  Illinois  drift, 
known  as  the  Old  Sangamon  Soil.  Later  other  ice  invasions  of  Illinois  oc- 
curred, but  they  covered  only  the  northern  and  northeastern  parts  of  the  state. 
(See  State  Map  in  Bulletin  123,  Iowan  and  Wisconsin  glaciations.)  These 
ice  sheets  did  not  reach  Sangamon  county,  but  immense  quantities  of  finely 
ground  rock  (rock  flour)  were  carried  south  by  the  waters  from  the  melt- 
ing ice  and  deposited  on  the  flood  plains  of  the  large  streams,  where  it  was 
picked  up  by  the  wind  and  carried  oyer  and  deposited  upon  the  land,  burying 
the  glacial  material  of  the  Illinois  glaciation  and  the  Sangamon  soil  to  a 
depth  of  from  5 to  50  feet  or  more,  the  deeper  deposit  being  nearer  and  on 
the  east  side  of  the  streams  and  opposite  the  greatest  width  of  bottom  land. 
This  wind-blown  material,  called  loess,  represents  a mixture  of  all  kinds  of 
material  over  which  the  glacier  passed. 

Near  the  Sangamon  river  three  layers  of  this  deposit  may  be  distinguished. 
The  lower  .one  is  typical  loess,  containing  shells  and  lime  concretions.  Above 
this  is  a stratum  of  sand  of  varying  thickness,  which  is  overlain  by  a more 
clayey  form  of  loess  that  was  probably  deposited  during  the  Wisconsin  gla- 
ciation. 

The  Sangamon  soil  may  sometimes  be  seen  in  cuts  as  a somewhat  dark  or 
bluish  sticky  clay,  or  as  a weathered  zone  of  yellowish  or  brownish  clay. 

More  recently  the  wind  has  blown  sand  from  the  flood  plains  of  the  large 
streams  onto  the  adjacent  upland,  thus  giving  rise  to  10.9  square  miles  of 
sandy  soils.  After  the  loessial  material  was  deposited  over  the  surface  of 
the  country  it  was  mixed  with  organic  matter  to  a greater  or  less  extent,  and 
thus  gradually  changed  into  soil.  Surface  washing  has  made  additional 
modifications. 

Table  1 shows  the  area  of  each  type  of  soil  in  the  country  and  its  percent- 
age of  the  total  area. 

It  will  be  noted  that  more  than  half  of  the  entire  county  is  covered  with 
the  common  prairie  land,  known  as  brown  silt  loam,  while  the  black  clay  loam, 
sometimes  called  “black  gumbo”,  occupying  the  flat  upland  prairie,  is  the 
second  most  extensive  type. 

Nearly  12  percent  of  the  county  consists  of  yellow-gray  silt  loam,  the  un- 
dulating upland  soil  once  covered  with  timber ; and  the  more  rolling  yellow 
silt  loam,  also  timber  upland,  is  about  half  as  extensive. 

Six  other  upland  types  aggregate  only  about  3 percent  of  the  county,  and 
nearly  9 percent  consists  of  bottom  land. 


4 


Soil  Report  No.  4 

Table  1 — Soil  Types  'ob  Sangamon  County 


[September, 


Soil 

type 

No. 

Name  of  type 

Area  in 
square 
miles 

Area  in 
acres 

Percent 

of 

total  area 

426 

(a)  Upland  Prairie  Soils 

Brown  silt  loam 

468.47 

299,817 

53.87 

420 

Black  clay  loam 

137.18 

87,801 

15.77 

428 

Brown-gray  silt  loam  on  tight  clay  . 

2.60 

1,665 

.30 

425.1 

Black  silt  loam  on  clay 

10.83 

6,928 

1.24 

434 

(b)  Upland  Timber  Soils 

Yellow-gray  silt  loam 

103.85 

66,460 

11.93 

435 

Yellow  silt  loam  

54.23 

34,709 

6.23 

432 

Light  gray  silt  loam  on  tight  clay 

3.75 

2,402 

.42 

464 

Yellow-gray  sandy  loam  

4.64 

2,971 

.53 

465 

Yellow  sandy  loam 

4.85 

3,102 

.55 

481 

Dune  sand 

1.43 

914 

.15 

1426 

(c)  Bottom  Land 

Deep  brown  silt  loam 

77.65 

49,696 

8.93 

Total  area . . 

869.48 

556,467 

100.00 

The  accompanying  maps  show  the  location  and  boundary  lines  of  every 
type  of  soil  in  the  county,  even  down  to  areas  of  a few  acres;  and  in  Table 
2 are  reported  the  amounts  of  organic  carbon  (the  best  measure  of  the  or- 
ganic matter)  and  the  total  amounts  of  the  five  important  elements  of  plant 
food  contained  in  the  2 million  pounds  of  the  surface  soil,  corresponding  to 
the  plowed  soil  of  an  acre  about  62/$  inches  deep.  In  addition,  the  table 
shows  the  amount  of  limestone  present  (if  any)  or  the  amount  of  limestone 
required  to  neutralize  the  acidity  existing  in  the  soil.* 


THE  INVOICE  AND  INCREASE  OF  FERTILITY  IN  SANGAMON 
COUNTY  SOILS 

Soil  Analysis 

In  order  to  avoid  complication  and  confusion  in  the  practical  application 
of  the  technical  information  contained  in  this  report,  the  results  are  given  in 
the  most  simplified  form.  The  composition  reported  for  a given  soil  type 
is  as  a rule  the  average  of  many  analyses,  which,  like  most  things  in  nature, 
show  more  or  less  variation.  For  all  practical  purposes  the  average  is  most 
trustworthy  and  sufficient,  as  will  be  seen  from  Bulletin  123,  which  reports 
the  general  soil  survey  of  the  state,  and  in  which  are  reported  many  hundred 
individual  analyses  of  soil  samples  representing  twenty-five  of  the  most 
important  and  most  extensive  soil  types  in  the  state. 

The  chemical  analysis  of  the  soil  gives  the  invoice  of  fertility  actually 
present  in  the  soil  strata  sampled  and  analyzed,  but  the  rate  of  liberation  is 
governed  by  many  factors,  as  explained  in  the  Appendix.  As  there  stated, 
probably  no  agricultural  fact  is  more  generally  known  by  farmers  and  land- 

*The  figures  given  in  Table  2 (and  in  the  corresponding  tables  for  subsurface  and  sub- 
soil) are  the  averages  for  all  samples  analyzed,  with  the  single  exception  of  the  limestone 
for  three  samples  of  brown  silt  loam,  one  each  for  surface,  subsurface,  and  subsoil.  With 
seemed  unwise  to  include  the  abnormal  exception  in  making  the  averages,  type;  and  it 
this  exception,  no  limestone  was  found  in  analyzing  51  samples  of  this  soil 


SOIL  SURVEY  MAP  OF  SANG  AM  01 C1 

UNIVERSITY  OF  ILLINOIS  AGRICULTURAL  EXP  II 


LEGEND 


UPLAND  PRAIRIE  SOILS 

,2®  Brown  ailt  loam 


UPLAND  TIMBER  SOILS 

1 Yellow-gray  silt  loam 


20  Black  clay  loam 
*20  | ’ 

Black  silt  loam  on  clay 
28  Brown-gray  ailt  loam  on  tight  clay 


UPLAND  TIMBER  SOILS 

*6*-  Yellow-gray  sandy  I 


^35  Yellow  ai,t  ,0*m 
32  Light  gray  silt  loam  on  tight  clay 


1 2+65  I Yellow  sandy  loam 
8i  Dune  sand 


l^26|  Deep  brown  silt  loar 

Scale 


Sangamon  Counw 


S 


1912] 

owners  than  that  soils  differ  in  productive  power.  Even  tho  plowed  alike 
and  at  the  same  time,  prepared  the  same  way,  planted  the  same  day  with  the 
same  kind  of  seed,  and  cultivated  alike,  watered  by  the  same  rains  and  warmed 
by  the  same  sun,  nevertheless  the  best  acre  may  produce  twice  as  large  a 
crop  as  the  poorest  acre  on  the  same  farm,  if  not,  indeed,  in  the  same  field; 
and  the  fact  should  be  repeated  and  emphasized  that  the  productive  power  of 
normal  soil  in  humid  sections  depends  upon  the  stock  of  plant  food  contained 
in  the  soil  and  upon  the  rate  at  which  it  is  liberated. 

The  fact  may  be  repeated,  too,  that  crops  are  not  made  out  of  nothing. 
They  are  composed  of  ten  different  elements  of  plant  food,  every  one  of 
which  is  absolutely  essential  for  the  growth  and  formation  of  every  agricul- 
tural plant.  Of  these  ten  elements  of  plant  food,  only  two  (carbon  and  oxy- 
gen) are  secured  from  the  air  by  all  plants,  only  one  (hydrogen)  from  water, 
and  seven  from  the  soil,  altho  nitrogen,  one  of  these  seven  elements  secured 
from  the  soil  by  all  plants,  may  also  be  secured  from  the  air  by  one  class  of 
plants  (legumes),  in  case  the  amount  liberated  from  the  soil  is  insufficient; 
but  even  these  plants  (which  include  the  clovers,  peas,  beans,  alfalfa,  and 
vetches),  in  common  with  other  agricultural  plants,  secure  from  the  soil 
alone  six  elements  (phosphorus,  potassium,  magnesium,  calcium,  iron  and  sul- 
fur) and  also  utilize  the  soil  nitrogen  so  far  as  it  becomes  soluble  and  avail- 
able during  their  period  of  growth. 

Table  A in  the  Appendix  shows  the  requirements  of  large  crops  for  the 
five  most  important  plant-food  elements  which  the  soil  must  furnish.  (Iron 
and  sulfur  are  supplied  normally  from  natural  sources  in  sufficient  abundance, 
compared  with  the  amounts  needed  by  plants,  so  that  they  are  not  known 
ever  to  limit  the  yield  of  crops.) 

As  stated,  the  data  in  Table  2 represent  the  total  amounts  of  plant  food 
found  in  two  million  pounds  of  the.  surface  soil,  which  corresponds  to  an  acre 
of  soil  about  62/$  inches  deep,  including  at  least  as  much  soil  as  is  ordinarily 
turned  with  the  plow,  and  representing  that  part  of  the  soil  with  which  we 
incorporate  the  farm  manure,  limestone,  phosphate,  or  other  fertilizer  applied 
in  soil  improvement.  This  is  the  soil  stratum  upon  which  we  must  depend 
in  large  part  to  furnish  the  necessary  plant  food  for  the  production  of  the 
crops  grown,  as  will  be  seen  from  the  information  given  in  the  Appendix. 
Even  a rich  subsoil  has  little  or  no  value  if  it  lies  beneath  a worn-out  surface, 
but  if  the  fertility  of  the  surface  soil  is  maintained  at  a high  point,  then  the 
strong  and  vigorous  plants  will  have  power  to  secure  more  plant  food  from 
the  subsurface  and  subsoil  than  would  be  the  case  with  weak,  shallow-rooted 
plants. 

By  easy  computation  it  will  be  found  that  the  most  common  prairie  soil 
of  Sangamon  county  does  not  contain  more  than  enough  total  nitrogen  in 
the  plowed  soil  for  the  .production  of  maximum  crops  for  eight  rotations; 
while  the  upland  timber  soils  contain  as  an  average  less  than  one-half  as  much 
nitrogen  as  the  prairie  land. 

With  respect  to  phosphorus,  the  condition  differs  only  in  degree,  nine- 
tenths  of  the  soil  area  of  the  county  containing  no  more  of  that  element  than 
would  be  required  for  fifteen  crop  rotations  if  such  crop  yields  were  secured 
as  suggested  in  Table  A of  the  Appendix;  and  in  case  of  the  cereals  it  will 


6 


Soil  Report  No.  4 


[September, 


Table  2. — Fertility  in  the  Soils  ok  Sangamon  County,  Illinois 


Average  pounds  per  acre  in  2 million  pounds  of  surface  soil  (about  0 to  6%  inches) 


Soil 

Total 

Total 

Total 

Total 

Total 

Total 

Lime- 

Lime- 

type 

Soil  type 

organic 

nitro- 

phos- 

potas- 

magne- 

cal- 

stone 

stone 

No. 

carbon 

gen 

phorus 

sium 

sium 

cium 

present 

requir’d 

Upland  Praix 

•ie  Soils 

426 

Brown  silt  loam 

51680 

4070 

1030 

34620 

7470 

9280 

50 

420 

Black  clay  loam 

63570 

5040 

1330 

31870 

11090 

15990 

2850 

428 

Brown-gray  silt 

loam  on  tight 

clay  

30490 

2700 

680 

35530 

5320 

8630 

350 

425.1 

Black  silt  loam 

on  clay 

58260 

4800 

1120 

31360 

10440 

14750 

240 

Upla 

ind  Timber  Soils 

434 

Yellow-gray  silt 

loam. . 

26160 

2300 

1010 

35970 

5390 

7100 

30 

435 

Yellow  silt  loam 

10240 

920 

820 

40020 

7210 

6440 

470 

432 

Bight  gray  silt 

loam  on  tight 

clay 

19040 

1880 

720 

33000 

5280 

6740 

20 

464 

Y ello  w-gray 

sandy  loam.  . . 

15000 

1640 

720 

36980 

6540 

5960 

40 

465 

Yellow  sandy 

loam 

11580 

1260 

620 

36640 

5020 

4240 

840 

481 

Dune  sand.. 

9140 

780 

480 

23430 

3010 

4480 

20 

Swamp  and  Bottom-Land  Soils 


1426 

Deep  brown  silt  1 

loam..  •••  | 51140 

4450 

1630 

41350 

10630 

be  seen  that  about  three-fourths  of  the  phosphorus  taken  from  the  soil  is 
deposited  in  the  grain,  while  only  one- fourth  remains  in  the  straw  or  stalks. 

On  the  other  hand,  the  potassium  is  sufficient  for  25  centuries  if  only  the 
grain  is  sold,  or  for  425  years  even  if  the  total  crops  were  removed  and  noth- 
ing returned.  The  corresponding  figures  are  about  2,000  and  500  years  for 
magnesium,  and  about  10,000  and  200  years  for  calcium. 

Thus,  when  measured  by  the  actual  crop  requirements  for  plant  food,  po- 
tassium is  no  more  limited  than  magnesium  and  calcium,  and,  as  explained 
in  the  Appendix,  with  these  elements  we  must  also  consider  the  heavier  loss 
by  leaching. 

These  general  statements  relating  to  the  total  quantities  of  plant  food  in 
the  plowed  soil  certainly  emphasize  the  fact  that  the  supplies  of  some  of 
these  necessary  elements  of  fertility  are  extremely  limited  when  measured  by 
the  needs  of  large  crop  yields  for  even  one  or  two  generations  of  people. 

The  variation  among  the  different  soil  types  with  respect  to  their  content 
of  important  plant-food  elements  is  also  very  marked.  Thus,  the  prairie 
soils  contain  from  three  to  five  times  as  much  nitrogen  as  the  timber  lands 
of  the  same  topography;  and  the  black  clay  loam,  the  richest  prairie  land, 
contains  twice  as  much  phosphorus  as  the  poorest  upland  soils.  (The  black 
clay  loam  of  the  middle  Illinois  glaciation  is  lower  in  phosphorus  than  the 
corresponding  type  in  the  more  recent  formations,  as  the  early  and  the  late 
Wisconsin.) 

On  the  other  hand,  the  most  significant  fact  revealed  by  the  investigation 
of  Sangamon  county  soils  is  the  low  phosphorus  content  of  the  common 


tor  COUNTY  R-  6 w 

ANGAMON  COUNTY 

URAL  EXPERIMENT  STATION 


LEGEND 

I UPLAND  PRAIRIE  SOILS 
46e  Brown  silt  loam 

l~^kl  Black  clay  loam 
| aL  | Black  silt  loam  on  clay 

Brown -gray  silt  loam  on  tight  c 

UPLAND  TIMBER  SOILS 
Bffl Yellow-gray  silt  loam 

| xg^ellow  silt  loam 

Light  gray  silt  loam  on  tight  cU 

I 64-  I 

| 1 Yellow-gray  sandy  loam 

| a65^|  Yellow  sandy  loam 
81  Dune  sand 


ia-26  Deep  brown  silt  loam 


Sangamon  County 


7 


1912] 

brown  silt  loam  prairie,  a type  of  soil  which  covers  more  than  one-half  of  the 
entire  county.  The  market  value  of  this  land  is  about  $200  an  acre,  and  yet 
an  application  of  $30  worth  of  fine-ground  raw  rock  phosphate  would  double 
the  phosphorus  content  of  the  plowed  soil.  Such  an  application  properly 
made  would  also  double  the  yield  of  clover  in  the  near  future;  and,  if  the 
clover  was  then  returned  to  the  soil  either  directly  or  in  farm  manure,  the 
combined  effect  of  phosphorus  and  nitrogenous  organic  matter  with  a good 
rotation  of  crops  would  in  time  double  the  yield  of  corn  on  most  farms. 

The  average  yield  of  corn  for  Sangamon  county  for  the  ten  years  1902 
to  1911  was  40.9  bushels  per  acre;*  yet  this  county  occupies  a most  favored 
position  in  the  most  southern  lobe  of  the  corn  belt  of  the  United  States. 
Meanwhile,  Boone  county,  on  the  Wisconsin  line,  nearly  200  miles  farther 
north,  has  averaged  41.5  bushels  of  corn  per  acre  during  the  same  ten  years. 

With  4,000  pounds  of  nitrogen  in  the  soil  and  an  inexhaustible  supply  in 
the  air,  with  34,000  pounds  of  potassium  in  the  same  soil  and  with  practically 
no  acidity,  the  economic  loss  in  farming  such  land  with  only  1,000  pounds 
of  total  phosphorus  in  the  plowed  soil  can  be  appreciated  only  by  the  man 
who  fully  realizes  that  the  crop  yields  could  be  doubled  by  adding  phosphorus, 
— and  without  change  of  seed  or  season  and  with  very  little  more  work  than  is 
now  devoted  to  the  fields. 

Fortunately,  some  definite  field  experiments  have  already  been  conducted 
on  this  most  extensive  type  of  soil  in  Sangamon  county,  and  also  for  longer 
periods  on  similar  soil  in  several  other  counties,  as  at  Virginia  in  Cass  county, 
at  Urbana  in  Champaign  county,  at  Sibley  in  Ford  county,  and  at  Blooming- 
ton in  McLean  county. 

Results  op  Field  Experiments  at  Auburn 

A field  of  ten  acres  of  common  prairie  land  was  selected  on  the  farm  of 
Mr.  B:  F.  Workman,  about  five  miles  west  of  Auburn,-  on  which  experiments 
were  begun  in  1905.  The  field  was  divided  into  two  series  of  plots,  corn 
being  grown  on  one  series  for  two  years  and  then  on  the  other  series, 
while  the  first  series  grew  oats  one  year  and  clover  the  next,  thus  providing 
for  a four-year  rotation  of  corn,  corn,  oats,  and  clover,  corn  being  repre- 
sented every  year,  and  the  oats  and  clover  in  alternate  years.  No  experi- 
mental data  were  secured  from  Series  100  during  the  first  two  years,  but  a 
crop  of  cowpeas  was  grown  and  plowed  under  on  all  plots  in  that  series  in 
1906. 

In  Table  3 are  recorded  the  results  secured  from  eight  plots  in  each  series, 
four  of  these  plots  having  received  applications  of  raw  rock  phosphate,  while 
the  other  four  received  no  phosphate,  but  were  otherwise  treated  the  same. 

It  is  of  special  interest  to  note  that  the  effect  of  phosphorus  on  the  corn 
crop  is  marked  whenever  the  seasonal  conditions  are  favorable  for  corn. 
Thus,  when  the  plots  not  receiving  phosphorus  have  produced  50  bushels 
or  more  per  acre,  the  increase  from  phosphorus  has  averaged  from  7.8  bushels 
in  1907  to  11.0  bushels  in  1908,  and  to  16.9  bushels  in  1911 ; but,  when  cer- 
tain other  factors  of  influence  have  held  the  yield  of  corn  below  50  bushels, 
phosphorus  has  produced  little  or  no  effect,  except  for  the  first  year,  when 
the  low  yield  was  due  to  a poor  stand  of  corn  and  not  to  adverse  weather 


'Statistical  Report,  Illinois  State  Board  of  Agriculture,  December  1,  1911,  page  36. 


8 


Soil  Report  No.  4 


[Sept,  ’inber, 


Table  3 — Experiments  with  Raw  Rock  Phosphate  on  Brown  Silt  Loam  Prairie, 
Auburn  Field 


Crops  and  yields  per  acre 

Without 

phosphorus 

With 

phosphorus 

Average 

gain 

for 

Year 

Plot  No 

2 

3 

4 

5 

6 

7 

8 

9 

phos- 

phorus 

100 

1905 

No  experiment 

200 

1905 

Corn,  bu. 

41.7 

39.3 

41.7 

42.1 

48.1 

46.3 

48.9 

49.7 

7.0 

100 

1906 

Cowpeas  (turned) 

200 

1906 

Corn,  bu 

42.1 

40.6 

34.9 

38.4 

42.9 

41.3 

39.8 

37.6 

1.4 

100 

1907 

Corn,  bu 

54.1 

61.9 

64.5 

61.1 

68.6 

68.1 

69,6 

66.4 

7.8 

200 

1907 

Oats,  bu 

26.6 

26.1 

25.9 

24.2 

35.9 

30.5 

31.3 

36.7 

7.9 

100 

1908 

Corn,  bu 

39.0 

513 

52.6 

38.5 

54.1 

59.2 

592 

53  0 

11.0 

200 

1908 

Clover,  tons 

.91 

2.12 

1.69 

.58 

.77 

.85 

1.98 

2.19 

.12 

100 

1909 

Oats,  bu 

43  1 

48.4 

52  0 

43.3 

44.7 

50.5 

55  5 

55.8 

3.7 

200 

1909 

Corn,  bu 

430 

48.3 

41.4 

32.8 

36.2 

25.8 

39.2 

48.5 

3.9 

100 

1910 

Clover,  tons 

2.31 

1.76 

2.25 

3.23 

3.06 

3.06 

1.01 

200 

1910 

Corn,  bu 

46.0 

49.5 

45.5 

38.6 

40.8 

44.6 

39.9 

58.6 

1.1 

100 

1911 

Corn,  bu 

48.2 

60.6 

40.0 

51  0 

57.5 

761 

65.9 

680 

16.9 

200 

1911 

Oats,  bu 

40.6 

43.0 

43.0 

36.6 

43.3 

45.8 

55.0 

59.1 

10.0 

{ Corn,  bu 5.9 

Average  gain  for  phosphorus  < Oats,  bu 7.2 

f Clover,  tons 57 


{ Corn,  bu 5.9 

Average  gain  for  phosphorus  < Oats,  bu 7.2 

f Clover,  tons 57 


The  cost  of  phosphorus  per  acre  per  annum  is  $1.87^;  but  during  the  seven  years 
the  increase  produced  has  not  only  more  than  paid  the  total  cost,  but  the  phosphorus 
content  of  the  treated  land  has  been  increased  from  about  1000  pounds  to  1300 
pounds  per  acre  of  plowed  soil. 

conditions.  As  an  average  of  these  four  years,  phosphorus  has  increased  the 
yield  of  corn  by  10.7  bushels  per  acre ; but  when  the  poor  years  are  included, 
the  average  increase  is  reduced  to  5.9  bushels,  this  figure  representing  the 
average  of  twenty-eight  different  comparable  tests. 

The  three  crops  of  oats  showed  an  average  increase  of  7.2  bushels,  and 
the  two  clover  crops  averaged. .57  ton  more  hay  on  the  phosphated  land. 

On  the  whole,  the  data  from  favorable  seasons  strongly  indicate  a cumula- 
tive or  increasing  effect  from  the  phosphate  treatment,  as  we  have  reason  to 
expect,  and  as  is  shown  in  the  latest  crops  of  corn,  oats,  and  clover,  the  in- 
crease amounting  to  about  25  percent  for  oats,  34  percent  for  corn,  and  48 
percent  for  clover. 

It  should  be  noted  that  the  phosphate  has  already  more  than  paid  its 
cost;  but  of  equal  importance,  at  least,  is  the  fact  that  the  soil  is  being 
positively  enriched  in  that  element;  and  after  a few  more  rotations  the 
amount  applied  for  each  year  may  be  very  greatly  reduced. 

On  Plots  2,  4,  7,  and  9 some  cover  crop,  such  as  cowpeas  or  clover,  has 
usually  been  seeded  between  the  corn  rows  at  the  time  of  the  last  cultivation. 
In  many  cases  this  has  decreased  the  yield  of  corn  for  that  year,  and  the 
data  thus  far  secured  do  not  justify  the  practice  in  central  or  northern  Illi- 
nois, especially  where  oats  follow  corn. 

Since  1908  crop  residues,  including  the  corn  stalks  and  oat  straw,  have 
been  returned  to  Plots  2 and  7,  and  the  second  crop  of  clover  was  plowed 


4f6*f  I Yellow-gray  sandy  !< 
*g5s  I Yellow  sandy  loam 


SI 


1^-26  Deep  brown  silt  I 


^NGAMON  COUNTY 

URAL  EXPERIMENT  STATION 


MACON  COU 


Sangamon  County 


9 


1912] 

under  in  1908,  and  all  clover  except  the  seed  in  1910,  on  these  plots.  The 
results  thus  far  secured  are  not  sufficient  to  justify  drawing  conclusions  in 
regard  to  this  practice,  but  it  may  be  noted  that  the  largest  yield  of  corn 
•during  the  seven  years  was  on  Plot  7 in  1911. 

Plots  5 and  6 receive  no  organic  manures;  but  farm  manure  has  been 
applied  to  the  clover  sod  and  plowed  under  for  corn,  since  1907,  on  plots 
3,  4,  8,  and  9,  the  rate  of  application  being  as  many  tons  of  fresh  manure 
as  the  number  of  tons  of  air-dry  produce  from  the  respective  plots.  As  an 
average,  the  manure  has  increased  the  yield  of  corn  by  4.6  bushels  (1907  to 
1911)  and  the  yield  of  oats  by  7.7  bushels  (1909  to  1911). 

Results  op  Field  Experiments  at  Virginia 

The  Virginia  experiment  field  was  established  in  1902,  on  a ten-acre 
tract  of  land  belonging  to  the  farm  of  Mr.  George  Conover,  about  three  miles 
southeast  of  Virginia,  in  Cass  county,  on  brown  silt  loam  prairie,  somewhat 
above  the  average  of  the  type  in  productive  power. 

A three-year  rotation  was  begun  on  three  different  series  of  plots  in  order 
that  each  crop  might  be  represented  every  year.  During  the  first  six  years 
corn,  oats,  and  cowpeas  were  grown,  but  since  1908  the  rotation  has  been 
corn,  oats,  and  clover. 

As  an  average  of  two  tests  each  year,  for  the  first  7 years  (1902  to 
1908),  phosphorus,  applied  at  the  rate  of  25  pounds  per  acre  per  annum  in 
200  pounds  of  steamed  bone  meal,  produced  increases  in  yield  per  acre 
amounting  to  6.8  bushels  of  corn  (from  67.3  to  74.1  bushels);  while  the 
average  yield  of  oats  was  increased  by  .4  bushel  (from  43.9  to  44.3  bushels), 
and  the  average  yield  of  hay  was  increased  by  only  .04  ton  (from  2.13  to 
2.17  tons  per  acre). 

During  the  next  three  years  (1909  to  1911)  the  phosphorus  increased 
the  average  yields  by  10.5  bushels  of  corn  (from  70.2  to  80.7  bushels),  by 
13. 1 bushels  of  oats  (43.3  to  56.4  bushels),  and  by  .69  ton  of  hay  (1.42  to 
2. 1 1 tons  per  acre). 

It  is  of  interest  to  compare  the  seven  years’  results  at  Auburn  with  the 
first  seven  years’  results  at  Virginia,  the  two  fields  being  on  the  same  soil 
type  in  the  same  soil  area.  When  the  Virginia  experiments  were  begun,  one 
ton  of  steamed  bone  meal,  containing  250  pounds  of'  phosphorus  (which  is 
the  amount  applied  to  one  acre  in  ten  years  at  Virginia),  cost  less  than  $25, 
but  in  recent  years  the  price  has  been  advanced  to  $28  to  $30  per  ton.  Thus, 
at  safe  prices  for  produce,  the  bone  meal  fell  far  short  of  paying  its  cost 
during  the  first  seven  years  at  Virginia,  altho  it  much  more  than  paid  for 
the  annual  expense  during  the  next  three  years. 

At  Auburn  two  and  one-half  times  as  much  phosphorus  is  applied  in  raw 
rock  phosphate  at  $7.50  per  ton,  but  the  annual  cost  is  only  $1.87^  per 
acre,  compared  with  $2.50  to  $3.00  for  the  bone  meal  used  at  Virginia. 

On  the  other  hand,  the  results  ultimately  secured  at  Virginia  were  to  be 
expected,  because  the  chemical  analysis  of  the  soil  shows  that  phosphorus  is 
not  abundant,  and  its  continued  use  must  finally  produce  marked  increases  in 
crop  yields  in  good  systems  of  farming.  The  fact  is  that  the  first  limiting 
element  on  the  Virginia  fiej/i  was  not  phosphorus  but  nitrogen;  and,  this 
being  the  case,  no  marked  effect  could  be  produced  by  phosphorus  until  the 
/ 
f 

/ 


10  Soil  Report  No.  4 [September, 

nitrogen  was  relatively  increased,  which  has  been  gradually  accomplished 
by  the  use  of  legume  crops  and  farm  manure. 

In  another  series  of  experiments  on  the  Virginia  field,  commercial  nitro- 
gen is  applied  in  a four-year  rotation  of  corn,  corn,  oats,  and  wheat.  Count- 
ing the  corn  at  35  cents  a bushel,  oats  at  30  cents,  and  wheat  at  70  cents,  we 
find  that  100  pounds  of  nitrogen  per  acre  per  annum  (in  dried  blood)  pro- 
duced $42.31  increase  in  ten  years;  the  yearly  addition  of  25  pounds  of 
phosphorus  in  200  pounds  of  steamed  bone  meal  raised  the  increase  to  $58.96 ; 
and  40  pounds  of  potassium  per  annum,  together  with  the  nitrogen  and 
phosphorus,  raised  the  total  increase  to  $60.67. 

If  we  count  the  cost  at  15  cents  a pound  for  nitrogen,  10  cents  a pound 
for  phosphorus,  and  6 cents  a pound  for  potassium,  we  find  that  for  each  dol- 
lar invested  the  nitrogen  paid  back  28  cents,  the  phosphorus  67  cents,  and 
the  potassium  7 cents.  As  an  average  of  the  four  years  1908  to  i9ii,the 
phosphorus,  costing  $2.50  per  annum,  paid  back  $3.15  under  these  conditions. 

During  six  of  the  ten  years,  corn  was  grown  in  both  of  the  rotation  sys- 
tems at  Virginia.  In  the  four-year  rotation,  without  legumes  or  manure, 
the  average  yield  was  50.4  bushels  of  corn  per  acre  where  lime  and  bone  meal 
were  applied,  but,  where  these  materials  were  applied  in  the  three-year  rota- 
tion, the  six-year  average  yield  of  corn  was  74.6  bushels  in  the  grain  system, 
with  some  crop  residues  plowed  under,  and  77.0  bushels  per  acre  where  farm 
manure  was  applied  in  addition  to  the  lime  and  phosphorus. 

Thus  legumes  in  rotation  and  some  crop  residues  plowed  under  in  grain 
farming  increased  the  six-year  average  yield  of  corn  by  24.2  bushels,  and 
farm  manure  and  legumes  in  rotation  increased  the  yield  by  26.6  bushels; 
while  100  pounds  of  commercial  nitrogen  in  about  800  pounds  of  dried  blood, 
costing  $15  to  $20  per  acre  per  annum,  increased  the  yield  by  only  19.5 
bushels.  (The  lime  and  phosphorus  were  provided  alike  on  all  plots  involved 
in  these  comparisons.) 

At  least  two  very  important  lessons  are  taught  by  these  results  from  the 
Virginia  field : First,  when  nitrogen  has  become  the  limiting  element  in  a 

soil,  nothing  else  can  take  its  place,  and,  even  tho  phosphorus  may  also 
be  deficient,  its  addition  will  not  produce  marked  or  profitable  results  until 
provision  is  made  to  raise  the  nitrogen  limit.  Second,  the  growing  of  legumes 
in  rotation  on  the  farm  and  the  use  of  crop  residues  or  farm  manure  may 
produce  even  better  results  than  high-priced  commercial  nitrogen. 

Results  of  Field  Experiments  at  Urbana 

A three-year  rotation  of  corn,  oats,  and  clover  was  begun  on  the  North 
Farm  at  the  University  of  Illinois  in  1902,  on  three  fields  of  typical  brown 
silt  loam  prairie  land  which,  after  twenty  years  or  more  of  pasturing,  had 
grown  corn  in  1895,  1896  and  1897  (when  careful  records  were  kept  of  the 
yields  produced),  and  had  then  been  cropped  with  clover  and  grass  on  one 
field,  oats  on  another,  and  oats,  cowpeas,  and  corn  on  the  third  field,  till  1901. 

As  an  average  of  the  three  years  1902  to  1904,  phosphorus  increased  the 
crop  yield  per  acre  by  .68  ton  of  clover,  8.8  bushels  of  corn,  and  1.9  bushels 
of  oats. 

During  the  second  three  years,  1905-1907,  phosphorus  produced  average 
increases  of  .79  ton  of  clover,  13.2  bushels  of  corn,  and  11.9  bushels  of  oats. 


Sangamon  County 


11 


1912] 

During  the  third  course  of  the  rotation,  1908-1910,  the  average  increases 
produced  by  phosphorus  were  1.05  tons  of  clover,  18.7  bushels  of  corn,  and  8.4 
bushels  of  oats. 

For  convenient  reference  the  results  are  summarized  in  Table  4. 


Table  4. — Effect  of  Phosphorus  on  Brown  Silt  Eoam  at  Urbana 
(Average  increase  per  acre) 


Rotation 

Years 

Corn, 

bu. 

Oats, 

bu. 

Clover, 

tons 

Value  of 
increase 

Cost  of 
treatment* 

First 

1902,-3,-4 

8.8  I 

1.9 

.68 

$ 7.73 

$ 7.50 

Second ... 

1905,-6,-7 

13.2 

11.9 

.79 

12.93 

7.50 

Third 

1908,-9,  10 

18.7 

8.4 

1.05 

15.37 

7.17 

*Prices  used  are  35  cents  a bushel  for  corn,  30  cents  for  oats,  $6.00  a ton  for  clover 
hay,  10  and  3 cents  a pound  for  phosphorus  in  bone  meal  and  rock  phosphate,  respec- 
tively. 


Plate  1.  Wheat  in  1911  on  Urbana  Field 
Cover  Crops  and  Crop  Residues  Plowed  Under 
Average  Yield,  35.2  Bushels  Per  Acre 


12 


Soil  Report  No.  4 


[September, 


Wheat  is  grown  on  the  University  South  Farm  in  a rotation  experiment 
started  more  recently.  As  an  average  of  the  last  four  years,  1908-1911,  raw 
rock  phosphate  (with  no  previous  applications  of  bone  meal)  has  increased 
the  yield  of  wheat  by  10.3  bushels  per  acre;  and  here  too  the  phosphorus  has 
paid  back  about  twice  its  cost,  as  an  average  of  the  last  four  years,  the  cost 
being  $1,873/2,  and  the  value  of  the  increase  $3.28  per  acr£  per  annum,  wheat 
being  valued  at  70  cents  a bushel  and  other  crops  as  noted  above.  These 
are  the  average  results  from  two  systems  of  farming,  one  known  as  grain 
farming,  and  the  other  as  live-stock  farming. 

In  the  grain  system  of  farming,  the  yield  of  wheat  in  1911  was  35.2 
bushels  per  acre  where  cover  crops  and  crop  residues  have  been  plowed  under 
without  the  use  of  phosphorus;  but  where  rock  phosphate  has  been  used  the 
average  yield  was  50.1  bushels  in  the  same  system.  (See  Plates  1 and  2.) 


Plate  2.  Wheat  in  1911  on  Urbana  Field 
Cover  Crops  and  Crop  Residues  Plowed  Under 
Fine-ground  Rock  Phosphate  Applied 
Average  Yield,  50.1  Bushels  Per  Acre 


Sangamon  County 


13 


1912] 

In  the  live-stock  farming,  the  yield  of  wheat  in  1911  was  34.2  bushels 
where  manure  and  cover  crops  are  used  without  phosphate,  and  51.8  bushels, 
as  an  average  where  rock  phosphate  is  used  in  connection  with  the  live-stock 
system.  (See  Plates  3 and  4.) 

These  results  emphasize  the  cumulative  effect  of  permanent  systems  of 
soil  improvement. 

Results  of  Experiments  on  Sibley  Field 

Table  5 gives  results  obtained  during  the  past  ten  years  from  the  Sibley 
soil  experiment  field,  located  in  Ford  county  on  typical  brown  silt  loam  prairie 
of  the  Illinois  corn  belt. 

Previous  to  1902  this  land  had  been  cropped  with  corn  and  oats  for  many 
years  under  a system  of  tenant  farming  and  the  soil  had  become  somewhat 
deficient  in  active  organic  matter.  While  phosphorus  was  the  limiting  ele- 


. Plate  3.  Wheat  in  1911  on  Urbana  Field 
Cover  Crops  and  Farm  Manure  Plowed  Under 
Average  Yield,  34.2  Bushels  Per  Acre 


14 


Soil  Report  No.  4 


[September, 


ment  of  plant  food,  the  supply  of  nitrogen  becoming  available  annually  was 
but  little  in  excess  of  the  phosphorus,  as  is  well  shown  by  the  corn  yields 
for  1903,  when  phosphorus  produced  an  increase  of  8 bushels,  nitrogen  with- 
out phosphorus  produced  no  increase,  but  nitrogen  and  phosphorus  increased 
the  yield  by  15  bushels. 

After  six  years  of  additional  cropping,  however,  nitrogen  appears  to  have 
become  the  most  limiting  element,  the  increase  in  1907  being  9 bushels  from 
nitrogen  and  only  5 bushels  from  phosphorus,  while  both  together  produced 
an  increase  of  33  bushels  of  corn.  By  comparing  the  corn  yields  for  the  four 
years  1902,  1903,  1906  and  1907,  it  will  be  seen  that  the  untreated  land  has 
apparently  grown  less  productive,  whereas  on  land  receiving  both  phosphorus 
and  nitrogen  the  yield  has  appreciably  increased,  so  that  in  1907,  when  the 
untreated  rotated  land  produced  only  34  bushels  of  corn  per  acre,  a yield  of 


Plate  4.  Wheat  in  1911  on  Urbana  Field 
Cover  Crops  and  Farm  Manure  Plowed  Under 
Fine-ground  Rock  Phosphate  Applied 
Average  Yield,  51.8  Bushels  Per  Acre 


Sangamon  County 


15 


1912] 

72  bushels,  or  more  than  twice  as  much,  was  produced  where  lime,  nitrogen, 
and  phosphorus  had  been  applied,  altho  these  two  plots  produced  exactly 
the  same  yield  (57.3  bushels)  in  1902. 

Even  in  the  unfavorable  season  of  1910,  the  highest  yielding  plot  exceeded 
that  of  1902,  while  the  untreated  land  produced  less  than  half  as  much.  The 
prolonged  drouth  of  1911  resulted  in  almost  a failure  of  the  corn  crop,  but 
nevertheless  the  effect  of  soil  treatment  is  seen.  Phosphorus  appears  to  have 
been  the  first  limiting  element  again  in  1909,  1910,  and  1911. 

In  the  lower  part  of  Table  5 are  shown  the  total  values  per  acre  of  the 
ten  crops  from  each  of  the  ten  different  plots,  the  amounts  varying  from 
$147.41  to  $227.46;  also  the  value  of  the  increase  produced  above  the  un- 
treated land,  corn  being  valued  at  35  cents  a bushel,  oats  at  30  cents  and 
wheat  at  70  cents.  Phosphorus  without  nitrogen  produced  $27.74  in  addi- 
tion to  the  increase  by  lime;  and,  with  nitrogen,  phosphorus  produced 


Table  5.— Crop  Yields  in  Soil  Experiments,  Sibley  Field 


Brown  silt  loam  prairie 
Early  Wisconsin  glaciation 

Corn 

1902 

Corn  I Oats 
1903  1904 

Wheat 

1905 

Corn 

1906 

Corn 

1907 

Oats 

1908 

Wheat 

1909 

Corn 

1910 

Corn 

1911 

Plot 

Soil  treatment 
applied 

Bushels  per  acre 

101 

None 

57.3 

50.4 

74.4 

29.5 

36.7 

33.9 

25.9 

25.3 

26.6 

20.7 

102 

Lime 

60.0 

54.0 

74.7 

31.7 

39.2 

38.9 

24.7 

28.8 

34.0 

22.2 

103 

Eime,  nitrogen 

60.0 

54.3 

77.5 

32.8 

41.7 

48.1 

36.3 

19.0 

29.0 

22.4 

104 

Lime,  phosphorus 

61.3 

62.3 

92.5 

36.3 

44.8 

43.5 

25.6 

32.2 

52.0 

31.6 

105 

Lime,  potassium 

56.0 

49.9 

74.4 

30.2 

37.5 

34.9 

22.2 

23.2 

34.2 

21.6 

106 

Lime,  nitrogen, 

phosphorus 

57.3 

69.1 

88.4 

45.2 

68.5 

72.3 

45.6 

33.3 

55.6 

35.3 

107 

Lime,  nitrogen, 

potassium 

53.3 

51.4 

75.9 

37.7 

39.7 

51.1 

42.2 

25.8 

46.2 

20.1 

108 

Lime,  phosphorus, 
potassium 

58.7 

60.9 

80.0 

39.8 

41.5 

39.8 

27.2 

28.5 

43.0 

31.8 

109 

Lime,  nitrogen, 
phosphorus, 
potassium 

58.7 

65.9 

82.5 

48.0 

69.5 

80.1 

52.8 

35.0 

58.0 

35.7 

110 

Nitrogen, 

phosphorus, 
potassium 

60.0 

60.1 

85.0 

48.5 

63.3 

72.3 

44.1 

30.8 

64.4 

31.5 

Value  oe  Crops  Per  Acre  in  Ten  Years 


Plot 

Soil  treatment  applied 

Total  value 
of  ten  crops 

Value  of 
increase 

101 

None  ■ 

$147.41 

102 

L,ime 

159.07 

$11.66 

103 

Lime,  nitrogen 

159.83 

12.42 

104 

Lime,  phosphorus. 

186.81 

39.40 

105 

Lime,  potassium 

148.29 

.88 

106 

Lime,  nitrogen,  phosphorus 

220.49 

73.08 

107 

Lime,  nitrogen,  potassium 

171.51 

24.10 

108 

Lime,  phosphorus,  potassium 

176.46 

29.05 

109 

Lime,  nitrogen,  phosphorus,  potassium 

227.46 

80.05 

110 

Nitrogen,  phosphorus,  potassium 

217.31 

69.90 

16 


Soil  Report  No.  4 


[September, 


$60.66  in  addition  to  the  increase  by  lime  and  nitrogen.  The  results  show 
that  in  23  cases  out  of  40  the  addition  of  potassium  decreased  the  crop  yields. 

By  comparing  Plots  101  and  102,  and  also  109  and  no,  it  will  be  seen 
that  the  average  increase  by  lime  was  $10.90,  or  more  than  $1.00  an  acre 
a year,  suggesting  that  the  time  is  near  when  limestone  must  be  applied  to 
these  brown  silt  loam  soils. 


Results  of  Experiments  on  Bloomington  Field 

Space  is  taken  to  insert  Table  6,  giving  all  of  the  results  thus  far  obtained 
from  the  Bloomington  soil  experiment  field,  which  is  also  located  on  the 
brown  silt  loam  prairie  soil  of  the  Illinois  corn  belt. 

The  general  results  of  the  ten  years’  work  on  the  Bloomington  field  tell 
the  same  story  as  those  from  the  Sibley  field.  The  rotations  differed  by  the 
use  of  clover  and  by  discontinuing  the  use  of  commercial  nitrogen,  after  1905, 
on  the  Bloomington  field,  in  consequence  of  which  phosphorus  without  com- 
mercial nitrogen  (Plot  104)  produced  an  even  larger  increase  (80.62)  than 
was  produced  by  phosphorus  over  nitrogen  on  the  Sibley  field  (see  Plots  103 
and  106). 

It  should  be  stated  that  a draw  runs  near  Plot  no  on  the  Bloomington 
field  and  the  crops  on  that  plot  are  sometimes  damaged  by  overflow  or  im- 
perfect drainage;  also  that  in  1902  the  stand  of  corn  on  the  Bloomington  field 
was  poor,  tho  fairly  uniform.  Otherwise  all  results  reported  in  Tables 
5 and  6,  including  200  tests,  are  considered  reliable,  and  they  furnish  much 
information  and  instructive  comparisons. 

Wherever  nitrogen  was  provided,  either  by  direct  application  or  by  the 
use  of  legume  crops,  the  addition  of  the  element  phosphorus  produced  very 
marked  increases,  the  average  value  being  $70.64  for  the  ten  years,  or  $7.06 
an  acre  a year.  This  is  $4.56  above  its  cost  in  200  pounds  of  steamed  bone 
meal,  the  form  in  which  is  was  applied  to  these  fields.  On  the  other  hand, 
the  use  of  phosphorus  without  nitrogen  will  not  maintain  the  fertility  of  the 
soil  (see  Plots  104  and  106,  Sibley  field)  ; and  a liberal  use  of  clover  or  other 
legumes  is  suggested  as  the  only  practical  and  profitable  method  of  supplying 
the  nitrogen,  the  clover  to  be  plowed  under,  either  directly  or  as  manure, 
preferably  in  connection  with  the  phosphorus  applied,  especially  if  raw  rock 
phosphate  is  used. 

From  the  best  treated  plots  140  pounds  per  acre  of  phosphorus  have  been 
removed  from  the  soil  in  the  ten  crops.  This  is  equal  to  12  percent  of  the 
total  phosphorus  contained  in  the  surface  soil  of  an  acre  of  the  untreated 
land.  In  other  words,  if  such  crops  could  be  grown  for  80  years  they  would 
require  as  much  phosphorus  as  the  total  supply  in  the  ordinary  plowed  soil. 
The  results  plainly  show,  however,  that  without  the  addition  of  phosphorus 
such  crops  cannot  be  grown  year  after  year.  Where  no  phosphorus  was 
applied,  the  crops  removed  only  95  pounds  of  phosphorus  in  ten  years,  equiva- 
lent to  only  8 percent  of  the  total  amount  (1,200  pounds)  in  the  surface  soil 
at  the  beginning  (1902).  The  total  phosphorus  applied  from  1902  to  1911 
amounted  to  250  pounds  per  acre. 


1912 ] 


Sangamon  County 


17 


Tabus  6.— Crop  Yields  in  Soil  Experiments,  Bloomington  Eield 


Brown  silt  loam 
prairie;  early 
Wisconsin 
glaciation 

Corn 

1902 

Corn 

1903 

Oats 

1904 

Wheat 

1905 

Clover 

1906 

Corn 

1907 

Corn 

1908 

Oats 

1909 

Clover 

1910t 

Wheat 

1911 

Plot 

Soil  treatment 
applied 

Bushels  or  tons  per  acre 

101 

None 

30.8 

63.9 

54.8 

30.8 

.39 

60.8 

40.3 

46.4 

1.56 

22.5 

102 

Lime 

37.0 

60.3 

60.8 

28.8 

.58 

63.1 

35.3 

53.6 

1.09 

22.5 

103 

Lime,  nitrogen  ... 

35.1 

59.5 

69.8 

30.5 

.46 

64.3 

36.9 

49.4 

(.83) 

25.6 

104 

Lime,  phosphorus. 
Lime,  potassium.. 

41.7 

73.0 

72.7 

39.2 

1.65 

82.1 

47.5 

63.8 

4.21 

57.6 

105 

37.7 

56.4 

62.5 

33.2 

.51 

64.1 

36.2 

45.3 

1.26 

21.7 

10C 

Lime,  nitrogen, 
phosphorus  

43.9 

77.6 

85.3 

50.9 

* 

78.9 

45.8 

72.5 

(1.67) 

60.2 

107 

Lime,  nitrogen, 
potassium 

40.4 

58.9 

66.4 

29.5 

.81 

64.3 

31.0 

51.1 

( -33) 

27.3 

108 

Lime,  phosphorus, 
potassium 

50.1 

74.8 

70.3 

37.8 

2.36 

81.4 

57.2 

59.5 

3.27 

54.0 

109 

Lime,  nitrogen, 
phosphorus,  po- 
tassium   

52.7 

80.9 

90.5 

51.9 

, 

88.4 

58.1 

64.2 

( -42) 

60.4 

110 

Nitrogen,  phos- 
phorus, potas- 
sium   . . 

52.3 

73.1 

71.4 

51.1 

* 

78.0 

51.4 

55.3 

( .60) 

61.0 

Value  of  Crops  per  Acre  in  Ten  Years 


Plot 

Soil  treatment  applied 

Total  value  of 
ten  crops 

Value  of 
increase 

101 

102 

£jone 

$147.90 

148.75 

Lime 

$ .85 

103 

104 

Lime,  nitrogen  (see  text) . . . . ....  

151.30 

3.40 

81.47 

Lime,  phosphorus 

229.37 

105 

Lime,  potassium 

149.43 

1.53 

106 

Lime,  nitrogen,  phosphorus  ....  

221 . 30 

73.40 

2.06 

107 

Lime,  nitrogen,  potassium  

149 . 96 

108 

Lime,  phosphorus,  potassium 

229.20 

81.30 

109 

Lime,  nitrogen,  phosphorus,  potassium 

225.57 

77.67 

110 

Nitrogen,  phosphorus,  potassium  . . . 

209.26 

61  36 

*Clover  smothered  out  by  previous  very  heavy  wheat  crop.  After  the  clover  hay 
was  harvested  all  ten  of  the  plots  were  seeded  to  cowpeas  and  the  crop  was  plowed 
under  later  on  all  plots  as  green  manure  for  the  1907  corn  crop. 

fThe  figures  in  parentheses  represent  bushels  of  clover  seed;  the  others,  tons  of 
clover  hay  (in  two  cuttings)  in  1910. 

The  Subsurface  and  Subsoil 

In  Tables  7 and  8 are  recorded  the  amounts  of  plant  food  in  the  subsurface 
and  the  subsoil,  but  it  should  be  remembered  that  these  supplies  are  of  little 
value  unless  the  top  soil  is  kept  rich.  Probably  the  most  important  informa- 
tion contained  in  Tables  7 and  8 is  that  the  upland  timber  soils  are  usually 
more  strongly  acid  in  the  subsurface  and  subsoil  than  in  the  surface,  thus 
emphasizing  the  importance  of  having  plenty  of  limestone  in  the  surface  soil 
to  neutralize  the  acid  moisture  which  rises  from  the  lower  strata  by  capillary 
action  during  the  periods  of  partial  drouth,  which  are  also  critical  periods 
in  the  life  of  such  plants  as  clover.  Thus,  while  the  common  brown  silt  loam 
prairie  soil  is  practically  neutral,  the  upland  soils  that  are  or  were  timbered 
are  already  in  need  of  limestone  as  a rule;  and,  as  already  explained,  they 
are  much  more  deficient  in  phosphorus  and  nitrogen  than  the  common  prairie. 


18 


Soil  Report  No.  4 


[September, 


Table  7.— Fertility  in  the  Soils  of  Sangamon  County,  Illinois 


Average  pounds  per  acre  in  4 million  pounds  of  subsurface  soil  (about  6%  to  20  inches) 


Soil 

Total  Total 

Total 

Total 

Total 

Total 

Lime- 

Lime- 

type 

Soil  type 

organic  nitro- 

phos- 

potas- 

magne- 

cal- 

stone 

stone 

No. 

carbon  gen 

phorus 

sium 

sium 

cium 

present 

requir’d 

Upland  Prairie  Soils 


426 

Brown  silt  loam 

69390 

5740 

1760 

68290 

17790 

17850 

100 

420 

Black  clay  loam 

73730 

5980 

2070 

63730 

22830 

27060 

3260 

428 

Brown-gray  silt 

loam  on  tight 

clay  

31680 

2760 

1120 

70660 

15180 

16880 

100 

425.1 

Black  silt  loam 

on  clay 

67660 

5540 

1780 

63500 

22140 

24800 

1760 

Upland  Timber  Soils 


434 

Yellow-gray  silt 

loam.. 

16880 

2150 

1760 

73250 

14570 

12170 

390 

435 

Yellow  silt  loam 

13460 

1540 

1880 

74780 

16920 

11400 

2080 

432 

Light  gray  silt 

loam  on  tight 

clay 

12000 

2040 

1280 

64440 

12640 

10000 

920 

464 

Y ellow  - gray 

sandy  loam . 

17880 

2000 

1760 

68480 

16560 

8920 

1760 

465 

Yellow  sandy 

loam 

5760 

1440 

1720 

77200 

19080 

9800 

400 

481 

Dune  sand 

5090 

690 

790 

41410 

6520 

8480 

30 

Swamp  and  Bottom-Land  Soils 

1426 

Deep  brown  silt 

I 6640 

loam.. 

73870 

2450 

78730 

| 23110 

I 22350 

| 650 

Table  8. — Fertility  in  the  Soils  of  Sangamon  County,  Illinois 
Average  pounds  per  acre  in  6 million  pounds  of  subsoil  (about  20  to  40  inches) 


Soil 

type 

No. 

Soil  type 

Total 

organic 

carbon 

Total 

nitro- 

gen 

Total 

phos- 

phorus 

Total 

potas- 

sium 

Total 

magne- 

sium 

Total 

cal- 

cium 

Lime- 

stone 

present 

Lime- 

stone 

requir'd 

Upland  Prairie  Soils 

426 

Brown  silt  loam 

39610 

4090 

2330  ' 

99930 

38860 

29750 

180 

420 

Black  clay  loam 

30710 

2990 

3070 

93620 

47060 

89180 

189150 

428 

Brown-gray  silt 

loam  on  tight 

clay 

37110 

3720 

2490 

97650 

36810 

33000 

270 

425.1 

Black  silt  loam 

on  clay 

28890 

3090 

2640 

96780 

39420 

41790 

30330 

Upland  Timber  Soils 


434 

Yellow-gray  silt 

loam 

17860 

2750 

3120 

105970 

34220 

19130 

5990 

435 

Yellow  silt  loam 

13320 

1710 

1950 

109680 

31470 

21780 

840 

432 

Light -gray  silt 

loam  on  tight 

clay 

28S00 

3300 

2220 

100740 

40020 

18540 

4140 

464 

Yellow  - gray 

sandy  loam.  . . 

14520 

1920 

3000 

110640 

28680 

27060 

50220 

465 

Yellow  sandy 

loam 

4980 

1920 

3060 

111900 

37560 

18660 

4680 

481 

Dune  sand 

7640 

1040 

1190 

62110 

9780 

12720 

50 

Sw 

amp  and  Bottom-Land  Soils 

1426 

Deep  brown  silt 

I 

loam 

| 58580 

5200 

2740 

116580 

32720 

30140 

1160 

Sangamon  County 


19 


1912] 


INDIVIDUAL  SOIL  TYPES 
(a)  Upland  Prairie  Soils 

This  class  of  soils  comprises  619  square  miles,  or  71  percent  of  the  entire 
area  of  the  county.  They  are  usually  dark  in  color  due  to  a large  organic-mat- 
ter content. 

The  accumulation  of  organic  matter  in  the  prairie  soils  is  due  to  the  growth 
of  prairie  grasses  whose  net  work  of  roots  has  been  protected  from  complete 
decay  by  imperfect  aeration,  due  to  the  covering  of  soil  and  the  moisture  it 
contained.  The  tops  have  been  burned  or  have  almost  completely  decayed. 
From  a sample  of  Champaign  county  virgin  sod  of  “blue  stem”,  one  of  the 
most  common  prairie  grasses,  it  was  determined  that  an  acre  of  this  soil  con- 
tained 13 y2  tons  of  roots  to  a depth  of  7 inches.  Many  of  these  roots  died 
each  year  and  by  partial  decay  formed  the  humus  of  these  dark  prairie  soils. 
In  upland  forests  no  such  quantity  of  roots  is  found  in  the  surface  soil.  The 
vegetable  matter  consists  of  leaves  and  twigs,  which  fall  upon  the  surface  and 
either  are  burned  by  forest  fires  or  undergo  complete  decay.  There  is  very 
little  chance  for  these  to  become  mixed  with  the  soil.  As  a result  the  organic- 
matter  content  has  been  lowered  by  the  growth  of  forests  until  in  some  parts 
of  the  state  a low  condition  of  apparent  equilibrium  has  been  reached.  All 
of  these  prairie  soils  can  be  improved  by  phosphorus  and  organic  manures, 
and  limestone  is  usually  needed.  The  different  types  differ  chiefly  in  degree 
of  richness,  as  is  seen  from  Table  2. 

Brown  Silt  Loam  (426) 

This  is  the  most  important  as  well  as  the  most  extensive  type  of  soil  in 
the  county,  covering  an  area  of  468.47  square  miles,  equivalent  to  299,817 
acres,  or  53.87  percent  of  the  entire  area. 

The  type  is  generally  sufficiently  rolling  for  fair  surface  drainage,  altho 
there  are  some  exceptions  where  the  land  is  so  flat  as  to  require  artificial 
drainage.  There  are  many  draws  or  swales,  which  are  frequently  “seepy” 
and  should  have  at  least  one  line  of  tile  to  carry  off  this  seepage  water. 
In  some  cases  two  lines  of  tile  may  be  necessary,  one  on  each  side.  In  the 
morainal  regions  and  along  some  of  the  small  streams,  the  brown  silt  loam 
L quite  rolling,  giving  a lighter  colored  and  shallower  phase  of  the  type. 

The  surface  soil,  o to  6^3  inches,  is  a brown  silt  loam,  varying  from  a 
yellowish  brown  on  the  more  rolling  areas  to  a dark  brown  or  black  on  the 
more  nearly  level  and  poorly  drained  areas.  The  physical  composition  varies 
to  some  extent  but  is  normally  a silt  loam  containing  from  about  70  to  80  per- 
cent of  the  different  grades  of  silt. 

The  clay  content,  usually  10  to  12  percent,  increases  as  the  type  approaches 
black  clay  loam  (420)  and  becomes  greatest  in  the  poorly  drained  areas.  The 
sand  varies  from  7 to  15  percent  and  increases  as  the  bottom  land  of  the  large 
streams  is  approached. 

The  organic  matter  varies  from  3 3/  to  5 percent,  with  an  average  of  4 y2 
percent,  or  45  tons  per  acre.  Where  the  type  passes  into  brown-gray  silt 
loam  on  tight  clay  (428),  the  organic  matter  becomes  lower.  The  growth 
of  forest  trees  on  the  upland  in  this  climate  reduces  the  organic  matter  and 
ultimately  changes  the  original  brown  prairie  soil  into  the  yellow-gray  silt 


20 


Soil  Report  No.  4 


[ September , 


loam  (434).  The  first  trees  to  invade  the  dark  prairie  soils  are  wild  cherry, 
hackberry,  ash,  black  walnut,  and  elm.  (A  black  walnut  soil  is  recognized 
generally  by  farmers  as  being  one  of  the  best  timber  soils.  It  still  contains, 
as  a rule,  a large  amount  of  the  organic  matter  that  accumulated  from  the 
prairie  grasses.) 

The  subsurface  is  represented  by  a stratum  varying  from  5 to  14  inches 
in  thickness,  the  great  difference  being  due  to  the  topography,  the  stratum 
being  thinner  on  the  more  rolling  areas  and  thicker  on  the  level  areas.  Its 
physical  composition  varies  in  the  same  way  as  the  surface  soil,  but  generally 
it  contains  a slightly  larger  amount  of  clay.  Locally,  the  subsurface  may 
become  quite  heavy,  as  where  the  type  grades  toward  the  black  silt  loam  on 
clay.  As  the  type  approaches  brown-gray  silt  loam  on  tight  clay  (428),  the 
subsurface  becomes  lighter  in  color  and  the  upper  subsoil  becomes  heavy  or 
contains  more  clay. 

The  color  of  the  subsurface  varies  from  a dark  brown  or  almost  black 
to  a light  brown  or  yellowish  brown.  In  general  it  becomes  lighter  with 
depth,  passing  gradually  into  the  yellow  subsoil.  The  color  is  due  to  the 
organic  matter  and  to  the  oxidation  of  the  iron. 

The  organic  matter  averages  1.8  percent. 

The  natural  subsoil  begins  at  from  12  to  21  inches  beneath  the  surface 
of  the  soil  and  extends  to  an  indefinite  depth,  but  is  usually  sampled  to  40 
inches.  It  varies  from  a yellow  to  a drabbish  yellow  clayey  silt.  In  the  more 
level  areas  it  is  of  a drab  color  mottled  with  yellow  blotches,  while  in  the 
more  rolling  areas  better  drainage  has  allowed  better  oxidation  of  the  iron  to 
take  place,  giving  the  yellow  to  brownish  yellow  color.  The  upper  8 to  12 
inches  of  the  subsoil  usually  contains  more  clay  than  the  lower  part,  the 
coarser  material  being  coarse  silt  or  fine  sand. 

The  subsoil  is  generally  pervious  to  water,  permitting  good  drainage.  Ex- 
ceptions are  found  where  the  type  grades  toward  the  brown-gray  silt  loam 
on  tight  clay  (428).  In  this  case  the  subsoil  becomes  much  less  pervious, 
forming  rather  a poor  phase  of  the  type. 

While  this  type  is  generally  in  fair  physical  condition,  yet  the  continuous 
growing  of  corn,  or  corn  and  oats,  with  the  burning  of  the  stalks  and  possibly 
the  oat  stubble,  is  destroying  the  tilth ; the  soil  is  becoming  more  difficult  to 
work,  runs  together  more,  and  aeration,  granulation,  absorption,  and  moist- 
ure movement  are  interfered  with.  This  condition  of  poor  tilth  is  becoming 
very  serious  on  many  farms  and  is  one  of  the  factors  that  limit  the  crop  yield. 

The  remedy  is  to  increase  the  organic-matter  content  by  plowing  under 
crop  residues  such  as  corn  stalks,  straw,  clover,  etc.,  instead  of  selling  them 
from  the  farm  or  burning  them,  as  is  often  practiced  at  present.  The  stalks 
should  be  thoroly  cut  up  with  a stalk  cutter  or  sharp  disk,  "and  turned  under. 
Likewise  the  straw  should  be  got  back  onto  the  land  in  some  practical  way, 
either  directly  or  in  manure.  Clover  should  be  one  of  the  crops  grown  in 
the  rotation,  and  it  should  be  plowed  under  directly  or  in  manure,  instead  of 
being  sold  as  hay,  except  where  manure  can  be  brought  back.  The  addition 
of  fresh  organic  matter  is  of  even  greater  importance  because  of  its  nitrogen 
content,  and  because  of  its  power,  as  it  decays,  to  liberate  potassium  from 
the  inexhaustible  supply  in  the  soil  and  phosphorus  from  the  phosphate  con- 
tained in  or  applied  to  the  soil,  as  seen  from  the  results  of  experiments  on 
the  Virginia  field  reported  above.  The  addition  of  limestone  to  this  soil  is 


Sangamon  County 


21 


W*\ 

also  becoming  important.  For  permanent  maintenance,  about  2 tons  of  . lime- 
stone and  y2  ton  of  fine-ground  rock  phosphate  should  be  applied  every  four 
or  five  years,  and  enough  organic  matter  should  be  plowed  under  to  furnish 
the  nitrogen  required  by  the  crops  desired,  as  shown  in  Table  A of  the  Ap- 
pendix. Heavier  initial  applications  of  phosphate  may  well  be  made. 

Black  Clay  Loam  (420) 

This  type  of  soil  (420)  represents  the  originally  swampy  and  poorly 
drained  areas  of  the  middle  Illinois  glaciation,  and  is  frequently  called 
“gumbo”  because  of  its  sticky  character.  Its  formation  in  these  low  places  is 
due  to  the  accumulation  of  organic  matter  and  the  washing  in  of  clay  and  fine 
silt  from  the  slightly  higher  adjoining  lands.  This  type  covers  137.18  square 
miles,  equivalent  to  87,801  acres,  and  occupies  15.77  percent  of  the  total  area 
of  the  county.  The  topography  is  so  flat  that  in  the  larger  areas  the  problem 
of  getting  a sufficient  outlet  for  drainage  has  caused  some  difficulty. 

The  surface  stratum  is  a black  granular  clay  loam  with  from  5 to  6 per- 
cent of  organic  matter.  The  average  is  5.5  percent,  or  55  tons  per  acre.  The 
wet  condition  of  this  soil  has  allowed  a greater  accumulation  of  organic  mat- 
ter than  on  the  more  rolling  areas  of  brown  silt  loam  (426). 

The  surface  soil  is  naturally  quite  granular,  and  hence  pervious  to  water. 
This  property  of  granulation  is  important  to  all  soils,  but  especially  to  heavy 
ones.  The  soil  is  kept  mellow,  and  if  the  granules  are  destroyed  by  puddling 
(as  by  working  or  the  tramping  of  stock  while  the  ground  is  wet),  they  will 
be  formed  again  by  freezing  and  thawing  or  by  moisture  changes  (wetting 
and  drying).  These  natural  agencies  produce  “slacking”,  as  the  process  is 
usually  termed.  If,  however,  the  organic  matter  or  lime  content  becomes 
low,  this  tendency  to  granulate  grows  less  and  the  soil  becomes  more  difficult 
to  work. 

The  subsurface  extends  to  a depth  of  from  10  to  16  inches  below  the  sur- 
face stratum.  It  differs  from  the  surface  in  color,  becoming  lighter  with 
depth,  the  lower  part  of  the  stratum  passing  into  a drab  or  yellowish  silty 
clay. 

It  is  quite  pervious  to  water,  due  to  the  jointing  or  checking  produced  by 
the  shrinkage  in  times  of  drouth.  The  amount  of  organic  matter  varies 
from  2.5  to  4 percent,  with  an  average  of  3.1  percent. 

The  subsoil  is  usually  a drab  or  dull  yellow  silty  clay,  but  locally  may  be 
a yellow  silt  or  clayey  silt.  As  a rule  the  iron  is  not  so  highly  oxidized,  due 
to  poor  drainage.  The  subsoil  is  checked  and  jointed,  making  it  pervious  to 
water  and  easy  to  drain.  In  many  areas  the  subsoil  contains  large  numbers 
of  concretions  of  iron  hydrate  and  sometimes  of  limestone  (calcium  carbon- 
ate). 

This  type  presents  many  variations.  Here  as  elsewhere  the  boundary 
lines  between  different  soil  types  are  rtot  always  distinct,  but  types  frequently 
pass  from  one  to  the  other  very  gradually,  thus  giving  an  intermediate  zone 
of  greater  or  less  width.  Variations  between  black  clay  loam  (420)  and 
brown  silt  loam  (426)  are  very  likely  to  occur,  since  these  are  usually  ad- 
joining types.  This  gives  a lighter  phase  of  black  clay  loam  (420),  with  a 
smaller  organic-matter  content  than  the  average,  and  a heavier  phase  of 
brown  silt  loam  (426),  with  a larger  amount  of  organic  matter  than  usual. 
(In  composition,  the  gradation  zone  is  intermediate  between  the  two  normal 


22 


Soil  Report  No.  4 


[September, 


types  adjoining.)  Again,  in  some  areas  of  black  clay  loam  there  has  been 
•enough  silty  material  washed  in  from  the  surrounding  higher  lands  to  modify 
the  character  of  the  surface  soil.  This  change  is  taking  place  more  rapidly 
now  with  the  annual  cultivation  of  soil  than  formerly  when  washing  was 
largely  prevented  by  prairie  grass. 

Drainage  is  the  first  requirement  of  this  type,  which,  altho  it  has  but  little 
slope,  yet  affords  a good  chance  for  tile  drainage  because  of  its  perviousness. 
Keeping  the  soil  in  good  physical  condition  is  very  essential,  and  thoro  drain- 
age helps  to  do  this  to  a great  extent.  As  the  organic  matter  is  destroyed  by 
cultivation  and  nitrification  and  the  lime  removed  by  cropping  and  leaching, 
the  physical  condition  becomes  poorer,  and  consequently  the  working  of 
the  soil  more  difficult.  Both  the  organic  matter  and  the  lime  tend  to  develop 
granulation  in  the  soil.  The  former  should  be  maintained  by  turning  under 
manure,  clover,  and  crop  residues,  cornstalks  and  straw,  the  very  things  this 
land  needs,  instead  of  burning  them,  as  is  commonly  practiced.  Ground 
limestone  should  be  applied  when  needed  to  keep  the  soil  sweet. 

While  this  soil  is  one  of  the  best  in  the  state,  yet  the  clay  and  humus  con- 
tained in  it  give  it  the  property  of  shrinkage  and  expansion  to  such  a degree 
as  to  be  somewhat  objectionable  at  times.  When  the  soil  is  wet,  these  constit- 
uents expand,  and  when  the  moisture  evaporates  or  is  used  by  crops,  the  soil 
shrinks.  This  results  in  the  formation  of  cracks  up  to  two  inches  or  more 
in  width,  and  extending  with  lessening  width  to  a depth  of  a foot  or  more. 
These  cracks  allow  the  subsurface  and  subsoil  to  dry  out  rapidly.  They 
sometimes  “block  out”  the  hills  of  corn,  severing  the  roots  and  doing  consid- 
erable damage  to  the  crop.  While  cracking  may  not  be  prevented  entirely  in 
this  type,  yet  good  tilth  with  a soil  mulch  will  do  much  toward  that  end. 

Altho  this  soil  is  still  moderately  rich,  its  phosphorus  content  is  not  high, 
and  it  may  well  be  increased  to  at  least  2000  pounds  per  acre  in  the  plowed 
soil,  the  nitrogen  being  maintained  by  means  of  legume  crops  and  farm  ma- 
nure, as  explained  in  the  Appendix. 

Brozvn-Gray  Silt  Loam  on  Tight  Clay  (428) 

This  type  is  found  principally  in  the  southern  part  of  the  county  and  rep- 
resents a type  of  the  transition  zone  between  the  lower  and  the  middle  Illinois 
glaciations.  The  type  occurs  in  extensive  areas  in  the  counties  south  of  San- 
gamon county.  The  small  areas  in  Sangamon  county  usually  represent  some 
poorly  drained  places,  altho  in  the  northwest  part  of  the  county,  in  Town- 
ship 17  North,  and  Ranges  5,  6,  and  7 West,  there  are  areas  where  the  soil 
naturally  seems  to  have  a rather  tight  clay  subsoil. 

The  type  is  generally  flat,  with  poor  drainage,  principally  due  to  the  char- 
acter of  the  subsoil.  It  occupies  2.6  square  miles,  or  1665  acres,  only  .3  per- 
cent of  the  total  area. 

The  surface  soil,  o to  6^3  inches,  is  a light  brown  or  grayish  brown  silt 
loam,  containing  some  fine  sand  and  coarse  silt  which  give  it  a peculiar 
mealy  “feel.”  The  organic-matter  content  varies  from  2.2  to  3.5  percent, 
according  to  its  relation  to  other  types,  being  greater  where  it  approaches 
brown  silt  loam  (426)  or  black  silt  loam  on  clay  (425.1)  and  less  where  it 
passes  toward  yellow-gray  silt  loam. 

The  subsurface  is  represented  by  a stratum  from  10  to  12  inches  thick. 
The  color  varies  from  a brown  to  a gray  silt  loam,  or  the  upper  part  of  this 


Sangamon  County 


23 


1912] 

stratum  may  be  brown  and  the  lower  gray.  It  differs  in  physical  composition 
from  the  surface  in  having  less  organic  matter,  the  average  amount  being  1.3 
percent. 

The  subsoil  consists  of  a stratum  of  clay,  beginning  at  from  16  to  18 
inches  beneath  the  surface  and  varying  from  10  to  20  inches  in  thickness.  It 
is  frequently  underlain  by  pervious  silt. 

Primarily  this  soil  in  this  county  needs  good  drainage.  Lines  of  tile  must 
be  placed  nearer  each  other  than  in  brown  silt  loam,  because  of  the  almost 
impervious  character  of  the  subsoil.  Care  should  be  taken  to  increase  the 
organic  matter  by  proper  rotation  and  turning  under  crop  residues  or  farm 
manure.  Where  this  is  done,  the  phosphorus  content  also  should  be  increased 
by  liberal  use  of  fine-ground  rock  phosphate.  For  the  best  results,  limestone 
should  also  be  applied.  The  initial  application  may  well  be  from  3 to  5 tons 
per  acre,  and  subsequent  additions  about  2 tons  every  four  or  five  years. 

Black  Silt  Loam  on  Clay  (425.1) 

This  type  comprises  only  1.24  percent  of  the  area  of  the  county  but  covers 
a total  area  of  10.83  square  miles,  or  6,928  acres.  It  occurs  mostly  in  small 
areas  over  the  county,  usually  adjoining  areas  of  black  clay  loam  (420)  or 
brown-gray  silt  loam  on  tight  clay  (428).  As  a general  thing,  with  about  the 
same  topography  as  black  clay  loam  (420),  it  does  not  permit  of  as  good 
underdrainage,  because  of  the  fact  that  the  subsoil  is  somewhat  tight.  This 
is  especially  true  where  the  type  approaches  the  brown-gray  silt  loam  on  tight 
clay  (428). 

The  surface  soil,  o to  62/s  inches,  is  a black  silt  loam,  varying  on  the  one 
hand  toward  a black  clay  loam,  and  on  the  other  to  a brown-silt  loam.  When 
thoroly  drained,  it  is  naturally  granular  and  in  good  tilth,  but  the  same  pre- 
cautions must  be  taken  in  regard  to  this  type  as  with  black  clay  loam. 

The  organic-matter  content  is  about  the  same  as  that  of  the  black  clay, 
loam,  varying  from  5.5  to  6.5  percent  and  averaging  about  60  tons  per  acre 
in  the  surface  soil. 

The  subsurface  stratum  varies  from  8 to  14  inches  in  thickness,  and  in 
color  from  black  or  dark  brown  to  a drab  or  yellowish  drab,  becoming  lighter 
with  depth.  The  proportion  of  clay  increases  somewhat  with  depth,  and  us- 
ually the  lower  part  of  this  stratum  is  a clay.  The  subsoil  resembles  that 
of  the  black  clay  loam. 

This  soil  type  is  moderately  rich,  but  its  productive  power  can  be  increased 
by  means  of  phosphorus  and  fresh  organic  manures,  both  of  which  are  neces- 
sary if  permanent  systems  of  soil  maintenance  are  to  be  practiced.  Limestone 
also  should  be  applied,  especially  where  the  subsoil  is  devoid  of  that  important 
material. 

(b)  Upland  Timber  Soils 
Yellow-Gray  Silt  Loam  (434) 

This  type  occurs  in  the  outer  timber  belts  along  the  Sangamon  river  and 
its  tributaries,  covering  11.93  percent  of  the  county,  or  103.85  square  miles 
(66,460  acres).  The  topography  is  sufficiently  rolling  for  good  surface  drain- 
age without  much  tendency  to  wash  if  proper  care  is  taken. 

The  surface  soil,  o to  6^3  inches,  is  a gray  to  yellowish  gray  silt  loam, 
incoherent  and  mealy  but  not  granular.  The  amount  of  organic  matter  varies 
from  1.8  to  2.3  percent,  or  an  average  of  20  tons  per  acre. 


24 


Soil  Report  No.  4 


[September, 


The  subsurface  stratum  varies  from  3 to  10  inches  in  thickness,  the  great- 
est variation  being  due  to  topography.  In  color  it  is  a gray,  grayish  yellow, 
or  yellow  silt  loam,  somewhat  mealy  but  becoming  more  coherent  and  clayey 
with  depth,  with  only  .72  percent  of  organic  matter. 

The  subsoil  is  a yellow,  or  grayish  yellow  mottled,  clayey  silt  or  silty 
clay,  somewhat  plastic  when  wet,  but  friable  when  only  moist,  and  pervious 
to  water.  The  type  is  quite  variable,  due  to  the  fact  that  it  grades  into  so 
many  different  types.  There  is  frequently  a transition  zone  between  two 
types  and  this  gives  a variation  in  both. 

In  the  management  of  this  type  one  of  the  first  things  is  the  maintenance 
or  increase  of  organic  matter  in  order  to  give  better  tilth,  to  supply  or  liberate 
plant  food,  prevent  “running  together,”  and,  in  some  of  the  more  rolling 
phases,  to  prevent  washing.  Another  essential  is  the  application  of  ground 
limestone  in  order  to  grow  clover,  alfalfa,  and  other  legumes  more  success- 
fully. This  soil  is  also  deficient  in  phosphorus,  and  this  must  be  supplied 
in  any  system  of  profitable,  permanent  improvement  of  this  type.  The  chief 
difference  physically  between  this  soil  and  the  common  prairie  is  in  the 
smaller  amount  of  organic  matter  in  the  surface  and  subsurface  of  the  timber 
lands,  which,  consequently,  are  also  poorer  in  nitrogen  and  often  somewhat 
poorer  in  phosphorus,  because  the  nitrogen  is  contained  only  in  the  organic 
matter,  while  phosphorus  is  contained  in  both  organic  and  mineral  forms. 
Initial  applications  of  1 ton  of  fine-ground  phosphate  plowed  under  with 
clover  or  manure,  and  of  2 to  5 tons  of  limestone,  may  well  be  made,  with 
subsequent  applications  of  ton  of  phosphate  and  2 tons  of  limestone  per 
acre  every  four  or  five  years. 

Yellow  Silt  Loam  (435) 

This  type  covers  about  6.23  percent  of  the  area  of  the  county,  equivalent 
to  54.23  square  miles  or  34,709  acres.  It  occurs  on  the  inner  timber  belts 
along  the  streams  as  the  hilly  and  badly  eroded  land,  usually  only  in  narrow, 
irregular  strips  with  arms  extending  up  the  small  streams.  The  topography 
is  very  rolling  and  so  badly  broken  that  it  should  not  be  cultivated  as  a rule, 
because  of  the  danger  of  injury  from  washing. 

The  surface  soil,  o to  6^3  inches,  is  a yellow  or  grayish  yellow  pulveru- 
lent, mealy  silt  loam.  This  varies  a great  deal,  due  to  recent  washing.  In 
some  places  the  real  subsoil  may  be  exposed. 

The  typical  subsurface  varies  considerably  with  the  amount  of  washing. 
In  thickness  it  varies  from  o to  12  inches,  the  variation  being  due  to  the  re- 
moval of  the  surface  and  part  of  the  subsurface.  The  subsoil  is  a compact, 
yellow,  clayey  silt. 

In  the  management  of  this  type  the  most  important  thing  is  to  prevent 
general  surface  washing  and  gullying.  If  it  is  cropped  at  all,  a rotation  should 
be  practiced  that  will  require  a cultivated  crop  as  little  as  possible  and  allow 
a great  deal  of  pasture  and  meadow.  If  tilled,  the  land  should  be  plowed 
deeply  and  contours  should  be  followed  as  nearly  as  possible,  both  in  plowing 
and  planting.  Furrows  extending  up  and  down  the  slopes  should  be  avoided. 
Cultivation  should  be  done  in  the  same  direction  as  plowing.  Every  means 
should  be  employed  to  maintain  and  increase  the  organic-matter  content  to 
help  hold  the  soil  and  keep  it  in  good  physical  condition  so  it  will  absorb  a 
large  amount  of  water  and  thus  diminish  the  run-off.  (See  Circular  119.) 


Sangamon  County 


1912] 

When  this  soil  is  to  be  prepared  for  seeding  down,  it  may  well  be  treated 
with  five  tons  per  acre  of  ground  limestone,  in  order  to  encourage  the  growth 
of  clover  and  thus  to  make  possible  the  accumulation  of  nitrogen,  the  element 
in  which  this  type  is  most  deficient.  As  a rule  it  is  not  advisable  to  try  to 
enrich  this  soil  in  phosphorus,  because  of  the  fact  that  erosion  is  sure  to  occur 
to  some  extent,  dnd  the  phosphorus  supply  will  thus  be  renewed  from  the 
subsoil. 

One  of  the  most  profitable  crops  to  grow  on  this  land  is  alfalfa,  and  to  get 
this  well  started  requires  liberal  use  of  limestone,  thoro  inoculation,  and 
a moderate  application  of  farm  manure.  If  the  manure  is  not  available,  it  is 
well  to  apply  about  500  pounds  per  acre  of  acid  phosphate,  mix  it  with  the 
soil,  by  disking  if  possible,  and  then  plow  it  under,  the  5 tons  of  limestone 
being  applied  after  plowing  and  mixed  with  the  surface  soil  in  the  prepara- 
tion of  the  seed  bed.  The  special  purpose  of  this  treatment  is  to  give  the 
alfalfa  a quick  start  in  order  that  it  may  grow  rapidly  and  thus  protect  the 
soil  from  washing. 

Light  Gray  Silt  Loam  on  Tight  Clay  (432) 

Only  a comparatively  small  total  area  of  this  type  is  found  in  the  county. 
It  aggregates  .42  percent,  equivalent  to  3.75  square  miles  or  2402  acres.  The 
areas  are  generally  small,  distributed  irregularly  along  the  Sangamon  river, 
South  Fork,  and  Horse  Creek.  The  larger  areas  occur  in  Town  15,  Ranges 
3 and  4 West.  The  topography  is  flat,  with  poor  drainage,  altho  not  swampy. 
These  areas  were  usually  protected  from  the  prairie  fires  by  streams  or  broken 
land  on  the  southwest.  This  type  is  practically  all  cleared  of  the  white  oak, 
hickory,  black  jack,  and  post  oak  that  formerly  covered  it. 

The  surface  soil  is  a white  or  very  light-gray  silt  loam,  incoherent,  friable 
and  porous.  Round  iron  concretions  are  usually  present.  The  organic-mat- 
ter content  is  low,  being  about  1.6  percent,  or  16  tons  per  acre  6^3  inches 
deep. 

The  subsurface  is  a light  gray  silt  extending  to  a depth  of  16  to  18  inches, 
becoming  more  clayey  with  depth  and  containing  only  .5  percent  of  organic 
matter. 

The  subsoil  is  a tight,  compact,  clayey  silt,  yellow  with  gray  mottlings. 
Below  36  inches  the  subsoil  is  usually  coarser  and  more  pervious. 

This  soil  is  very  deficient  in  organic  matter  and  lacking  in  lime,  and  is 
necessarily  in  poor  physical  condition.  The  soil  runs  together  badly  and  does 
not  hold  moisture  well,  owing  to  the  strong  capillarity  in  the  surface  and  sub- 
surface strata.  In  the  management  of  this  soil,  ground  limestone  and  rock 
phosphate  should  be  added  and  the  content  of  organic  matter  increased  in 
every  practical  way.  Deep-rooting  crops,  such  as  red,  mammoth  or  sweet 
clover,  would  loosen  the  tight  clay  subsoil  as  well  as  supply  the  soil  with 
organic  matter  and  nitrogen.  Crop  residues  should  be  plowed  under,  by  all 
means,  to  bring  the  soil  into  better  tilth.  Where  not  well  drained,  alsike  will 
grow  better  than  red  clover,  and  pasturing  is  one  of  the  best  uses  of  this  land, 
altho  it  may  well  be  liberally  enriched  in  limestone  and  phosphorus  before 
seeding  down,  and  alsike  and  white  clover  should  be  included  in  the  mixture 
of  grass  seed. 


26 


Soil  Report  No.  4 


[September, 


Yellow-Gray  Sandy  Loam  (464) 

This  type  occupies  .53  percent  of  the  county,  or  4.64  square  miles  (2,971 
acres),  and  is  found  near  the  larger  streams,  the  sand  having  been  derived 
from  the  bottom  land  and  transported  by  the  wind.  It  occurs  mostly  on  the 
east  and  north  sides  of  the  bottom  land,  with  an  apparent  exception  where  the 
upland  on  the  south  side  of  the  Sangamon  river  juts  out  into  the  bottom  land 
in  Township  16  North,  Ranges  4 and  5 West.  These  broad  areas' extend  oufc 
far  enough  to  catch  the  sand  blown  up  by  the  westerly  winds. 

The  topography  varies  to  a considerable  extent,  in  places  resembling  that 
ordinarily  found  in  the  upland,  while  in  others  it  has  a dune  character. 

The  surface  soil,  o to  62/t,  inches,  is  a light  brownish  yellow  to  grayish- 
yellow  sandy  loam.  The  sand  is  mostly  medium  but  mixed  with  some  coarse 
and  considerable  fine  sand. 

The  subsurface  is  a yellowish  gray  or  yellow  sandy  loam  but  varies  a great 
deal,  in  some  places  being  only  a silty  material  covered  by  a layer  that  con- 
stitutes the  sandy  loam,  while  in  others  this  stratum  runs  into  sand  and  con- 
tinues partly  or  entirely  thru  the  subsoil. 

This  soil  is  low  in  organic  matter,  the  surface  containing  1.3  percent,  or 
13  tons  per  acre.  Care  must  be  taken  to  use  every  means  to  increase  the 
organic-matter  content.  This  is  especially  necessary  to  provide  nitrogen  for 
the  soil,  and,  secondarily,  to  liberate  plant  food  and  put  the  soil  in  better 
physical  condition. 

No  field  experiments  have  been  conducted  on  this  soil  type;  but  from  ex- 
periments on  more  sandy  land  at  Green  Valley  in  Tazewell  county  (see  Bul- 
letin 123),  it  is  doubtful  if  the  addition,  of  phosphorus  will  prove  profitable 
wherever  the  subsoil  is  very  sandy,  thus  permitting  a very  deep  feeding 
range  for  the  plant  roots.  From  2 to  5 tons  per  acre  of  limestone  should  be 
applied,  with  renewed  applications  of  2 tons  per  acre  every  four  or  five  years. 
Sufficient  legume  crops,  crop  residues,  or  farm  manure  should  be  plowed 
under  to  provide  the  nitrogen  needed  by  the  non-leguminous  crops  to  be 
grown  (see  Appendix).  This  soil  is  especially  well  adapted  to  alfalfa  when 
properly  treated  with  limestone  and  well  inoculated,  farm  manure  being  used 
to  give  the  alfalfa  a good  start. 

Yellow  Sandy  Loam  (465) 

This  type  covers  an  area  of  4,845  square  miles,  or  3,102  acres,  being  .55 
percent  of  the  area  of  the  county.  It  occurs  in  the  same  region  as  the  yellow- 
gray  sandy  loam  (464). 

The  topography  is  very  rolling  and  hilly.  Care  must  be  taken  to  prevent 
washing,  altho  there  is  not'  the  danger  from  this  cause  that  there  is  in  the  case 
of  silt  loams. 

The  surface  soil,  o to  62/$  inches,  is  a light  brown  to  yellow  sandy  loam. 
All  grades  of  sand  are  found,  but  medium  sand  predominates.  This  stratum 
contains  only  1 percent  of  organic  matter,  or  10  tons  per  acre. 

The  subsurface  varies  from  a yellow  sandy  loam  to  a sand,  and  this  sand 
continues  to  forty  inches.  As  a rule  this  land  should  be  left  in  forest,  but 
where  cropped  large  use  should  be  made  of  legumes.  While  the  surface  soil 
contains  a small  amount  of  limestone  (probably  in  the  form  of  light  pieces 
of  shells  blown  with  the  sand  from  the  bottom  lands),  liberal  use  of  ground 
limestone  would  be  helpful  for  growing  legumes,  especially  for  alfalfa. 


Sangamon  CountV 


27 


1912] 

Dune  Sand  (481) 

The  sand  dunes  occupy  part  of  the  upland  sandy  tracts  in  various  places, 
but  usually  only  small  isolated  areas,  the  largest  being  not  more  than  80  acres. 

The  entire  area  occupied  by  the  type  is  1.43  square  miles,  or  914  acres, 
constituting  only  .15  percent  of  the  county.  Dune  topography  characterizes 
this  type. 

The  surface  is  a light  brown  sand  passing  into  a yellow  sand  that  consti- 
tutes both  the  subsurface  and  subsoil.  The  organic- matter  content  is  ex- 
ceedingly low,  being  only  .4  percent,  or  4 tons  per  acre.  This  indicates  a low 
nitrogen  content,  and  every  practical  means  should  be  taken  to  increase  the 
organic  matter  for  the  purpose  of  furnishing  nitrogen  as  well  as  to  prevent 
blowing  of  soil. 

Liberal  use  of  limestone  (preferably  dolomite,  because  of  the  low  magne- 
sium content  of  this  soil)  is  especially  important  for  the  improvement  of  this 
sand  soil ; and  legumes  should  be  the  principal  crops  grown.  While  this  soil  is 
the  lowest  in  phosphorus  of  all  the  types  in  the  county,  it  is  very  doubtful  if 
any  form  of  phosphorus  can  be  applied  with  profit.  The  soil  is  abnormal  in 
physical  character,  being  so  open  and  porous  that  the  feeding  range  afforded 
the  plant  roots  is  very  great.  The  air  easily  penetrates  such  soil,  so  that  oxida- 
tion and  liberation  of  plant  food  occur  at  much  greater  depths  than  in  heavier 
soils.  Furthermore,  the  phosphorus  is  contained  in  both  organic  and  mineral 
forms,  and  the  mineral  phosphorus  may  be  associated  with  calcium  and  iron 
compounds  not  locked  up  in  the  sand  grains. 

Next  to  limestone  and  organic  matter,  the  addition  of  kainit  is  to  be 
recommended  for  the  improvement  of  this  sand  soil,  especially  to  get  a good 
start  with  alfalfa,  cowpeas,  or  other  legumes.  The  kainit  furnishes  soluble 
salts,  including  potassium  which,  tho  present  in  the  sand  in  considerable 
amount,  is  chiefly  locked  up  in  the  sand  grains.  (Any  one  interested  in  sand 
soil  is  advised  to  study  Bulletin  123.) 

(c)  Swamp  and  Bottom-Land  Soils 
Deep  Brown  Silt  Loam  ( 1426) 

The  bottom-land  soil  is  derived  from  material  washed  from  the  upland. 
It  must  therefore  have  some  relation  to  the  uplands.  It  differs  in  being  more 
variable  as  to  physical  composition  than  any  single  upland  type,  and  the 
brown  color  extends  into  it  to  greater  depth.  The  bottoms  along  streams 
vary  from  a few  rods  to  a mile  or  more  in  width.  These  lands  occupy  77.65 
square  miles,  equivalent  to  49,696  acres,  and  constitute  8.93  percent  of  the 
entire  area  of  the  county.  The  topography  is  flat  or  with  very  slight  undula- 
tions that  represent  old  stream  or  overflow  channels.  Better  drainage  is 
needed  in  much  of  this  area. 

The  surface  soil,  o to  6 2/t,  inches,  is  a brown  silt  loam  containing  from 
3-5  to  5-3  percent  of  organic  matter,  the  average  being  4.4  percent,  or  44  tons 
per  acre.  It  is  probably  easier  to  maintain  the  organic  matter  in  this  type 
than  in  the  upland  because  of  the  occasional  overflow  and  the  consequent 
deposition  of  material  rich  in  this  constituent.  The  physical  composition  of 
the  soil  varies  from  a clay  loam  to  a sandy  loam,  but  the  areas  of  these  ex- 
treme types,  especially  the  latter,  are  so  small  and  so  changeable  that  it  really 


28 


Soil  Report  No.  4 


[September, 


does  not  mean  very  much  to  show  them  on  the  map  as  the  next  flood  may 
change  their  boundaries. 

The  subsurface  is  brown  silt  loam,  becoming  lighter  with  depth.  It  con- 
tains an  average  of  3.2  percent  of  organic  matter. 

The  subsoil  is  a yellowish  drab  silt  loam,  varying  in  physical  composition 
either  to  a clayey  silt  or  to  a sandy  loam  or  even  a sand  in  the  lower  subsoil. 

The  type  is  quite  productive  where  proper  drainage  is  secured;  and  as  a 
rule  no  soil  treatment  is  recommended  except  good  farming.  Even  the  sys- 
tematic rotation  of  crops  is  not  important  where  the  land  overflows  occa- 
sionally, but  where  it  is  protected  from  overflow  a rotation  including  legume 
crops  should  be  practiced,  and  ultimately  provision  would  need  to  be  made 
for  the  enrichment  of  such  protected  land. 


Sangamon  County 


29 


1912] 


APPENDIX 

A study  of  the  soil  map  and  the  tabular  statements  concerning  crop  re- 
quirements, the  plant-food  content  of  the  different  soil  types,  and  the  actual 
results  secured  from  definite  field  trials  with  different  methods  or  systems 
of  soil  improvement,  and  a careful  study  of  the  discussion  of  general  prin- 
ciples and  of  the  descriptions  of  individual  soil  types,  will  furnish  the  most 
necessary  and  useful  information  for  the  practical  improvement  and  perma- 
nent preservation  of  the  productive  power  of  every  kind  of  soil  on  every 
farm  in  the  county. 

More  complete  information  concerning  the  most  extensive  and  import- 
ant soil  types  in  the  great  soil  areas  in  all  parts  of  Illinois  is  contained  in 
Bulletin  123,  “The  Fertility  of  Illinois  Soils,”  which  contains  a colored  gen- 
eral survey  soil  map  of  the  entire  state. 

Other  publications  of  general  interest  are : 

Bulletin  No.  76,  “Alfalfa  on  Illinois  Soils” 

Bulletin  No.  94,  “Nitrogen  Bacteria  and  Legumes” 

Bulletin  No.  115,  “Soil  Improvement  for  the  Worn  Hill  Lands  of  Illinois” 

Bulletin  No.  125,  “Thirty  Years  of  Crop  Rotation  on  the  Common  Prairie  Lands  of 
Illinois” 

Circular  No.  no,  “Ground  Limestone  for  Acid  Soils” 

Circular  No.  127,  “Shall  we  use  Natural  Rock  Phosphate  or  Manufactured  Acid  Phos- 
phate for  the  Permanent  Improvement  of  Illinois  Soils?” 

Circular  No.  129,  “The  Use  of  Commercial  Fertilizers” 

Circular  No.  149,  “Some  Results  of  Scientific  Soil  Treatment”  and  “Methods  and  Re- 
sults of  Ten  Years’  Soil  Investigation  in  Illinois” 

NOTE. — Information  as  to  where  to  obtain  limestone,  phosphate,  bone  meal,  and  po- 
tassium salts,  methods  of  application,  etc.,  will  also  be  found  in  Circulars  no  and  149. 


Soil  Survey  Methods 

The  detail  soil  survey  of  a county  consists  essentially  of  indicating  on 
a map  the  location  and  extent  of  the  different  soil  types;  and,  since  the 
value  of  the  survey  depends  upon  its  accuracy,  every  reasonable  means  is 
employed  to  make  it  trustworthy.  To  accomplish  this  object  three  things 
are  essential:  first,  careful,  well-trained  men  to  do  the  work;  second,  an  ac- 
curate base  map  upon  which  to  show  the  results  of  their  work:  and,  third, 
the  means  necessary  to  enable  the  men  to  place  the  soil-type  boundaries, 
streams,  etc.,  accurately  upon  the  map. 

The  men  selected  for  the  work  must  be  able  to  keep  their  location 
exactly  and  to  recognize  the  different  soil  types,  with  their  principal  varia- 
tions and  limits,  and  they  must  show  these  upon  the  maps  correctly.  A 
definite  system  is  employed  .in  checking  up  this  work.  As  an  illustration,  one 
soil  expert  will  survey  and  map  a strip  80  rods  or  160  rods  wide  and  any 
convenient  length,  while  his  associate  will  work  independently  on  another 
strip  adjoining  this  area,  and,  if  the  work  is  correctly  done,  the  soil  type 
boundaries  will  match  up  on  the  line  between  the  two  strips. 

An  accurate  base  map  for  field  use  is  absolutely  necessary  for  soil  map- 
ping. The  base  maps  are  made  on  a scale  of  one  inch  to  the  mile.  The 
official  data  of  the  original  or  subsequent  land  survey  are  used  as  a basis  in 
the  construction  of  these  maps,  while  the  most  trustworthy  county  map  avail- 
able is  used  in  locating  temporarily  the  streams,  roads,  and  railroads.  Since 
the  best  of  these  published  maps  have  some  inaccuracies,  the  location  of  every 
road,  stream,  and  railroad  must  be  verified  by  the  soil  surveyors,  and  cor- 


30 


Soil  Report  No.  4 


[September, 


reeled  if  wrongly  located.  In  order  to  make  these  verifications  and  correc- 
tions, each  survey  party  is  provided  with  an  odometer  for  measuring  dis- 
tances, and  a plane  table  for  determining  directions  of  roads,  railroads,  etc. 

Each  surveyor  is  provided  with  a base  map  of  the  proper  scale,  which  is 
carried  with  him  in  the  field ; and  the  soil-type  boundaries,  additional  streams, 
and  necessary  corrections  are  placed  in  their  proper  locations  upon  the  map 
while  the  mapper  is  on  the  area.  Each  section,  or  square  mile,  is  divided  into 
40-acre  plots  on  the  map,  and  the  surveyor  must  inspect  every  ten  acres  and 
determine  the  type  or  types  of  soil  composing  it.  The  different  types  are 
indicated  on  the  map  by  different  colors,  pencils  being  carried  in  the  field 
for  this  purpose. 

A small  augur  40  inches  long  forms  for  each  man  an  invaluable  tool  with 
which  he  can  quickly  secure  samples  of  the  different  strata  for  inspection. 
An  extension  for  making  the  augur  80  inches  long  is  taken  by  each  party, 
so  that  any  peculiarity  of  the  deeper  subsoil  layers  may  be  studied.  Each 
man  carries  a compass  to  aid  in  keeping  directions.  Distances  along  roads 
are  measured  by  an  odometer  attached  to  the  axle  of  the  vehicle,  while  dis- 
tances in  the  field  off  the  roads  are  determined  by  pacing,  an  art  in  which 
the  men  become  expert  by  practice.  The  soil  boundaries  can  thus  be  located 
with  as  high  a degree  of  accuracy  as  can  be  indicated  by  pencil  on  the 
scale  of  one  inch  to  the  mile. 


The  unit  in  the  soil  survey  is  the  soil  type,  and  each  type  possesses  more 
or  less  definite  characteristics.  The  line  of  separation  between  adjoining 
types  is  usually  distinct,  but  sometimes  one  type  grades  into  another  so 
gradually  that  it  is  very  difficult  to  draw  the  line  between  them.  In  such 
exceptional  cases,  some  slight  variation  in  the  location  of  soil-type  boundaries 
is  unavoidable. 

Several  factors  must  be  taken  into  account  in  establishing  soil  types. 
These  are  ( 1 ) the  geological  origin  of  the  soil,  whether  residual,  glacial, 
loessial,  alluvial,  colluvial,  or  cumulose;  (2)  the  topography,  or  lay  of  the 
land;  (3)  native  vegetation,  as  forest  or  prairie  grasses;  (4)  the  structure, 
or  the  depth  and  character  of  the  surface,  subsurface,  and  subsoil;  (5)  the 
physical  or  mechanical  composition  of  the  different  strata  composing  the  soil, 
as  the  percentages  of  gravel,  sand,  silt,  clay,  and  organic  matter  which  they 
contain;  (6)  the  texture,  or  porosity,  granulation,  friability,  plasticity,  etc.; 
(7)  the  color  of  the  strata;  (8)  the  natural  drainage;  (9)  agricultural 
value,  based  upon  its  natural  productiveness;  (10)  the  ultimate  chemical 
composition  and  reaction. 

The  common  soil  constituents  are  indicated  in  the  following  outline : 


Son,  Characteristics 


Organic 

Matter 


Constituents  of  Soils 

f Comprising  undecomposed  and  partially  decayed 
I vegetable  material 


Soil 

Constituents 


.001  mm.  to  .03  mm. 
. .03  mm.  to  1.  mm. 
. . 1.  mm.  to  32  mm. 
. . . 32.  mm.  and  oyer 


.001  mm.*  and  less 


Inorganic 

Matter 


*25  millimeters  equal  1 inch. 

Further  discussion  of  these  constituents  is  given  in  Circular  82, 


Sangamon  County 


31 


1912] 


Groups  of  Soil  Types 

The  following  gives  the  different  general  groups  of  soils : 

Peats — Consisting  of  35  percent  or  more  of  organic  matter,  sometimes 
mixed  with  more  or  less  sand  or  silt. 

Peaty  loams — 15  to  35  percent  of  organic  matter  mixed  with  much  sand 
and  silt  and  a little  clay. 

Mucks — 15  to  35  percent  of  partly  decomposed  organic  matter  mixed 
with  much  clay  and  some  silt. 

Clays — Soils  with  more  than  25  percent  of  clay,  usually  mixed  with  much 

silt. 

Clay  loams — Soils  with  from  15  to  25  percent  of  clay,  usually  mixed 
with  much  silt  and  some  sand. 

Bilt  loams — Soils  with  more  than  50  percent  of  silt  and  less  than  15 
percent  of  clay,  mixed  with  some  sand. 

Loams — Soils  with  from  30  to  50  percent  of  sand  mixed  with  much  silt 
and  a little  clay. 

Sandy  loams — Soils  with  from  50  to  75  percent  of  sand. 

Fine  sandy  loams — Soils  with  from  50  to  75  percent  of  fine  sand  mixed 
with  much  silt  and  little  clay. 

Sands — Soils  with  more  than  75  percent  of  sand. 

Gravelly  loams — Soils  with  15  to  50  percent  of  gravel  with  much  sand 
and  some  silt. 

Gravels — Soils  with  more  than  50  percent  of  gravel. 

Stony  loams — Soils  containing  a considerable  number  of  stones  over  one 
inch  in  diameter. 

Rock  outcrop — Usually  ledges  of  rock  having  no  agricultural  value. 

More  or  less  organic  matter  is  found  in  nearly  all  the  above  classes. 


Supply  and  Liberation  of  Plant  Food 

The  productive  capacity  of  land  in  humid  sections  depends  almost  wholly 
upon  the  power  of  the  soil  to  feed  the  crop;  and  this,  in  turn,  depends  both 
upon  the  stock  of  plant  food  contained  in  the  soil  and  upon  the  rate  at  which 
this  is  liberated,  or  rendered  soluble  and  available  for  use  in  plant  growth. 
Protection  from  weeds,  insects,  and  fungous  diseases,  tho  exceedingly  im- 
portant, is  not  a positive  but  a negative  factor  in  crop  production. 

The  chemical  analysis  of  the  soil  gives  the  invoice  of  fertility  actually 
present  in  the  soil  strata  sampled  and  analyzed,  but  the  rate  of  liberation  is 
governed  by  many  factors,  some  of  which  may  be  controlled  by  the  farmer, 
while  others  are  largely  beyond  his  control.  Chief,  among  the  important 
controllable  factors  which  influence  the  liberation  of  plant  food  are  lime- 
stone and  decaying  organic  matter,  which  may  be  added  to  the  soil  by  direct 
application  of  ground  limestone  and  farm  manure.  Organic  matter  may  be 
supplied  also  by  green-manure  crops  and  crop  residues,  such  as  clover,  cow- 
peas,  straw,  and  cornstalks.  The  rate  of  decay  of  organic  matter  depends 
largely  upon  its  age  and  origin,  and  it  may  be  hastened  by  tillage.  The 
chemical  analysis  shows  correctly  the  total  organic  carbon,  which  represents, 
as  a rule,  but  little  more  than  half  the  organic  matter;  so  that  20,000 
pounds  of  organic  carbon  in  the  plowed  soil  of  an  acre  correspond  to  nearly 


32 


Soil  Report  No.  4 


[September, 


20  tons  of  organic  matter.  But  this  organic  matter  consists  largely  of  the 
old  organic  residues  that  have  accumulated  during  the  past  centuries  because 
they  were  resistant  to  decay,  and  2 tons  of  clover  or  cowpeas  plowed  under 
may  have  greater  power  to  liberate  plant  food  than  the  20  tons  of  old,  inactive 
organic  matter.  The  recent  history  of  the  individual  farm  or  field  must  be 
depended  upon  for  information  concerning  recent  additions  of  active  organic 
matter,  whether  in  applications  of  farm  manure,  in  legume  crops,  or  in  grass- 
root  sods  of  old  pastures. 

Probably  no  agricultural  fact  is  more  generally  known  by  farmers  and 
landowners  than  that  soils  differ  in  productive  power.  Even  tho  plowed 
alike  and  at  the  same  time,,  prepared  the  same  way,  planted  the  same  day 
with  the  same  kind  of  seed,  and  cultivated  alike,  watered  by  the  same  rains 
and  warmed  by  the  same  sun,  nevertheless  the  best  acre  may  produce  twice 
as  large  a crop  as  the  poorest  acre  on  the  same  farm,  if  not,  indeed,  in  the 
same  field;  and  the  fact  should  be  repeated  and  emphasized  that  with  the 
normal  rainfall  of  Illinois  the  productive  power  of  the  land  depends  primarily 
upon  the  stock  of  plant  food  contained  in  the  soil  and  upon  the  rate  at  which 
it  is  liberated,  just  as  the  success  of  the  merchant  depends  primarily  upon 
his  stock  of  goods  and  the  rapidity  of  sales.  In  both  cases  the  stock  of  any 
commodity  must  be  increased  or  renewed  whenever  the  supply  of  such  com- 
modity becomes  so  depleted  as  to  limit  the  success  of  the  business,  whether 
on  the  farm  or  in  the  store. 

As  the  organic  matter  decays,  certain  decomposition  products  are  formed, 
including  much  carbonic  acid,  some  nitric  acid,  and  various  organic  acids, 
and  these  have  power  to  act  upon  the  soil  and  dissolve  the  essential  mineral 
plant  foods,  thus  furnishing  soluble  phosphates,  nitrates,  and  other  salts  of 
potassium,  magnesium,  calcium,  etc.,  for  the  use  of  the  growing  crop. 

As  already  explained,  fresh  organic  matter  decomposes  much  more  rap- 
idly than  the  old  humus,  which  represents  the  organic  residues  most  resistant 
to  decay  and  which  consequently  has  accumulated  in  the  soil  during  the 
past  centuries.  The  decay  of  this  old  humus  can  be  hastened  both  by  tillage, 
which  maintains  a porous  condition  and  thus  permits  the  oxygen  of  the  air 
to  enter  the  soil  more  freely  and  to  effect  the  more  rapid  oxidation  of  the 
organic  matter,  and  also  by  incorporating  with  the  old,  resistant  residues 
some  fresh  organic  matter,  such  as  farm  manure,  clover  roots,  etc.,  which 
decay  rapidly  and  thus  furnish  or  liberate  organic  matter  and  inorganic  food 
for  bacteria,  the  bacteria,  under  such  favorable  conditions,  appearing  to  have 
power  to  attack  and  decompose  the  old  humus.  It  is  probably  for  this  reason 
that  peat,  a very  inactive  and  inefficient  fertilizer  when  used  by  itself,  becomes 
much  more  effective  when  incorporated  with  fresh  farm  manure;  so  that, 
when  used  together,  two  tons  of  the  mixture  may  be  worth  as  much  as  two 
tons  of  manure,  but  if  applied  separately,  the  peat  has  little  value.  Bacterial 
action  is  also  promoted  by  the  presence  of  limestone. 

The  condition  of  the  organic  matter  of  the  soil  is  indicated  more  or  less 
definitely  by  the  ratio  of  carbon  to  nitrogen.  As  an  average,  the  fresh 
organic  matter  incorporated  with'  soils  contains  about  twenty  times  as  much 
carbon  as  nitrogen,  but  the  carbohydrates  ferment  and  decompose  much  more 
rapidly  than  the  nitrogenous  matter;  and  the  old  resistant  organic  residues, 
such  as  are  found  in  normal  subsoils,  commonly  contain  only  five  or  six  times 
as  much  carbon  as  nitrogen.  Soils  of  normal  physical  composition,  such 
as  loam,  clay  loam,  silt  loam,  and  fine  sandy  loam,  when  in  good  productive 


Sangamon  County 


33 


1912] 

condition,  contain  about  twelve  to  fourteen  times  as  much  carbon  as  nitrogen 
in  the  surface  soil ; while  in  old,  worn  soils  that  are  greatly  in  need  of  fresh, 
active,  organic  manures,  the  ratio  is  narrower,  sometimes  falling  below  ten  of 
carbon  to  one  of  nitrogen.  (Except  in  newly  made  alluvial  soils,  the  ratio 
is  usually  narrower  in  the  subsurface  and  subsoil  than  in  the  surface  stratum.) 

’It  should  be  kept  in  mind  that  crops  are  not  made  out  of  nothing.  They 
are  composed  of  ten  different  elements  of  plant  food,  every  one  of  which  is 
absolutely  essential  for  the  growth  and  formation  of  every  agricultural  plant. 
Of  these  ten  elements  of  plant  food,  only  two  (carbon  and  oxygen)  are 
secured  from  the  air  by  all  agricultural  plants,  only  one  (hydrogen)  from 
water,  and  seven  from  the  soil.  Nitrogen,  one  of  these  seven  elements 
secured  from  the  soil  by  all  plants,  may  also  be  secured  from  the  air  by  one 
class  of  plants  (legumes),  in  case  the  amount  liberated  from  the  soil  is  insuf- 
ficient; but  even  these  plants  (which  include  only  the  clovers,  peas,  beans,  and 
vetches,  among  our  common  agricultural  plants)  secure  from  the  soil  alone 
six  elements  (phosphorus,  potassium,  magnesium,  calcium,  iron  and  sulfur), 
and  also  utilize  the  soil  nitrogen  so  far  as  it  becomes  soluble  and  available 
during  their  period  of  growth. 

Plants  are  made  of  plant-food  elements  in  just  the  same  sense  that 
a building  is  made  of  wood  and  iron,  brick,  stone,  and  mortar.  Without 
materials,  nothing  material  can  be  made.  The  normal  temperature,  sunshine, 
rainfall,  and  length  of  season  in  central  Illinois  are  sufficient  to  produce 
50  bushels  of  wheat  per  acre,  100  bushels  of  corn,  100  bushels  of  oats,  and 
4 tons  of  clover  hay ; and,  where  the  land  is  properly  drained  and  properly 
tilled,  such  crops  would  frequently  be  secured  if  the  plant  foods  were  present 
in  sufficient  amounts  and  liberated  at  a sufficiently  rapid  rate  to  meet  the  abso- 
lute needs  of  the  crops. 

Crop  Requirements 

The  accompanying  table  shows  the  requirements  of  such  crops  for  the 
five  most  important  plant-food  elements  which  the  soil  must  furnish.  (Iron 
and  sulfur  are  supplied  normally  in  sufficient  abundance  compared  with  the 
amounts  needed  by  plants,  so  that  they  are  not  known  ever  to  limit  the  yield 
of  general  farm  crops  grown  under  normal  conditions). 


Table  A. — Plant  Pood  in  Wheat,  Corn.  Oats,  and  Clover 


Produce 

Nitro- 

gen, 

pounds 

Phos- 

phorus, 

pounds 

Potas- 

Magne- 

Cal- 

Kind 

Amount 

pounds 

pounds 

pounds 

Wheat,  grain 

SO  bu. 

71 

12 

13 

4 

1 

Wheat  straw 

2 yz  tons 

25 

4 

45 

4 

10 

Corn,  grain 

100  bu. 

100 

17 

19 

7 

1 

Corn  stover 

Corn  cobs  

3 tons 
% ton 

48 

6 

52 

10 

21 

Oats,  grain 

100  bu. 

66 

11 

16 

4 

2 

Oat  straw 

2^  tons 

31 

5 

52 

7 

15 

Clover  seed 

4 bu. 

7 

2 

3 

1 

1 

Clover  hay. . 

4 tons 

160 

20 

120 

31 

117 

Total  in  grain  and  seed 

244* 

42 

51 

16 

4 

Total  in  four  crops 

510* 

77 

322 

68 

168 

*These  amounts  include  the  nitrogen  contained  in  the  clover  seed  or  hay,  which, 
however,  may  be  secured  from  the  air. 


34 


Soil  Report  No.  4 


1 September', 


To  be  sure,  these  are  large  yields,  but  shall  we  try  to  make  possible  the 
production  of  yields  only  half  or  a quarter  as  large  as  these,  or  shall  we 
set  as  our  ideal  this  higher  mark,  and  then  approach  it  as  nearly  as  possible 
with  profit?  Among  the  four  crops,  corn  is  the  largest,  with  a total  yield 
o,f  more  than  six  tons  per  acre;  and  yet  the  100-bushel  crop  of  corn  is  often 
produced  on  rich  pieces  of  land  in  good  seasons.  In  very  practical  and 
profitable  systems  of  farming,  the  Illinois  Experiment  Station  has  produced, 
as  an  average  of  the  six  years  1905  to  1910,  a yield  of  87  bushels  of  corn 
per  acre  in  grain  farming  (with  limestone  and  phosphorus  applied,  and  with 
crop  residues  and  legume  crops  turned  under),  and  90  bushels  per  acre  in 
live-stock  farming  (with  limestone,  phosphorus,  and  manure). 

The  importance  of  maintaining  a rich  surface  soil  cannot  be  too  strongly 
emphasized.  It  is  well  illustrated  by  data  from  the  Rothamsted  Experiment 
Station,  the  oldest  in  the  world.  Thus  on  Broadbalk  field,  where  wheat  has 
been  grown  since  1844,  the  average  yields  for  the  ten  years  1892  to  1901 
were  12.3  bushels  per  acre  on  Plot  3 (unfertilized)  and  31.8  bushels  on 
Plot  7 (well  fertilized),  but  the  amounts  of  both  nitrogen  and  phosphorus 
in  the  subsoil  (9  to  27  inches)  were  distinctly  greater  in  Rot  3 than  in 
Plot  7,  thus  showing  that  the  higher  yields  from  Plot  7 were  due  to  the 
fact  that  the  plowed  soil  had  been  enriched.  In  1893  Plot  7 contained  per 
acre  in  the  surface  soil  (o  to  9 inches)  about  600  pounds  more  nitrogen  and 
900  pounds  more  phosphorus  than  Plot  3.  Even  a rich  subsoil  has  little 
value  if  it  lies  beneath  a worn-out  surface. 

Methods  of  Liberating  Plant  Pood 

Limestone  and  decaying  organic  matter  are  the  principal  materials  the 
farmer  can  utilize  most  profitably  to  bring  about  the  liberation  of  plant  food. 

The  limestone  corrects  the  acidity  of  the  soil  and  thus  encourages  the 
development  not  only  of  the  nitrogen-gathering  bacteria  which  live  in  the 
nodules  on  the  roots  of  clover,  cowpeas,.and  other  legumes,  but  also  the 
nitrifying  bacteria,  which  have  power  to  transform  the  insoluble  and  unavail- 
able organic  nitrogen  into  soluble  and  available  nitrate  nitrogen. 

At  the  same  time,  the  products  of  this  decomposition  have  power  to  dis- 
solve the  minerals  contained  in  the  soil,  such  as  potassium  and  magnesium, 
and  also  to  dissolve  the  insoluble  phosphate  and  limestone  which  may  be 
applied  in  low-priced  forms. 

Tillage,  or  cultivation,  also  hastens  the  liberation  of  plant  food  by  permit- 
ting the  air  to  enter  the  soil  and  burn  out  the  organic  matter;  but  it  should 
never  be  forgotten  that  tillage  is  wholly  destructive,  that  it  adds  nothing 
whatever  to  the  soil,  but  always  leaves  the  soil  poorer.  Tillage  should  be 
practiced  so  far  as  is  necessary  to  prepare  a suitable  seed-bed  for  root  devel- 
opment and  also  for  the  purpose  of  killing  weeds,  but  more  than  this  is 
unnecessary  and  unprofitable  in  seasons  of  normal  rainfall;  and  it  is  much 
better  actually  to  enrich  the  soil  by  proper  applications  or  additions,  including 
limestone  and  organic  matter  (both  of  which  have  power  to  improve  the 
physical  condition  as  well  as  to  liberate  plant  food)  than  merely  to  hasten 
soil  depletion  by  means  of  excessive  cultivation. 

Permanent  Soil  Improvement 

The  best  and  most  profitable  methods  for  the  permanent  improvement  of 
the  common  soils  of  Illinois  are  as  follows : 


Sangamon  County 


35 


1912] 


(1)  If  the  soil  is  acid,  apply  at  least  two  tons  per  acre  of  ground  lime- 
stone, preferably  at  times  magnesian  limestone  (CaC03MgC03),  which 
contains  both  calcium  and  magnesium  and  has  slightly  greater  power  to  cor- 
rect soil  acidity,  ton  for  ton,  than  the  ordinary  calcium  limestone  (CaC03)  ; 
and  continue  to  apply  about  two  tons  per  acre  of  ground  limestone  every  four 
or  five  years.  On  strongly  acid  soils,  or  in  preparing  the  land  for  alfalfa,  five 
tons  per  acre  of  ground  limestone  may  well  be  used  for  the  first  application. 

(2)  Adopt  a good  rotation  of  crops,  including  a liberal  use  of  legumes, 
and  increase  the  organic  matter  of  the  soil  either  by  plowing  under  the 
legume  crops  and  other  crop  residues  (straw  and  corn  stalks),  or  by  using 
for  feed  and  bedding  practically  all  the  crops  raised  and  returning  the 
manure  to  the  land  with  the  least  possible  loss.  No  one  can  say  in  advance 
what  will  prove  to  be  the  best  rotation  of  crops,  because  of  variation  in 
farms  and  farmers,  and  in  prices  for  produce,  but  the  following  are  suggested 
to  serve  as  models  or  outlines : 

First  year,  corn  (with  some  winter  legume,  such  as  red  clover,  alsike,  sweet  clover, 
or  alfalfa,  or  a mixture,  seeded  on  part  of  the  field  at  the  last  cultivation). 

Second  year,  oats  or  barley  or  wheat  (fall  or  spring)  on  one  part  and  cowpeas  or 
soybeans  where  the  winter  catch  crop  is  plowed  down  late  in  the  spring. 

Third  year,  wheat  or  oats  (with  clover  or  clover  and  grass). 

Fourth  year,  clover  or  clover  and  grass. 

Fifth  year,  wheat  and  clover  or  grass  and  clover. 

Sixth  year,  clover  or  clover  and  grass. 

Of  course  there  should  be  as  many  fields  as  there  are  years  in  the  rota- 
tion. In  grain  farming,  with  wheat  grown  the  third  and  fifth  years,  most  of 
the  coarse  products  should  be  returned  to  the  soil,  and  the  clover  may  be 
clipped  and  left  on  the  land  (only  the  clover  seed  being  sold  the  fourth  and 
sixth  years)  ; or,  in  live-stock  farming,  the  field  may  be  used  three  years  for 
timothy  and  clover  pasture  and  meadow  if  desired.  The  system  may  be 
reduced  to  a five-year  rotation  by  cutting  out  either  the  second  or  the  sixth 
year,  and  to  a four-year  system  by  omitting  the  fifth  and  sixth  years. 

With  two  years  of  corn,  followed  by  oats  with  clover-seeding  the  third 
year,  and  by  clover  the  fourth  year,  all  produce  can  be  used  for  feed  and 
bedding  if  other  land  is  available  for  permanent  pasture.  Alfalfa  may  be 
grown  on  a fifth  field  for  four  or  eight  years,  which  is  to  be  alternated  with 
one  of  the  four;  or  the  alfalfa  may  be  moved  every  five  years,  and  thus 
rotated  over  all  five  fields  every  twenty-five  years. 

Other  four-year  rotations  more  suitable  for  grain  farming  are : 

Wheat  (and  clover),  corn,  oats,  and  clover,  or  corn  (and  clover),  cowpeas,  wheat, 
and  clover.  (Alfalfa  may  be  grown  on  a fifth  field  and  rotated  every  five  years, 
the  hay  being  sold.) 

Good  three-year  rotations  are : 

Corn,  oats,  and  clover;  corn,  wheat,  and  clover;  or  wheat  (and  clover),  corn  (and 
clover),  and  cowpeas,  in  which  two  cover  crops  and  one  regular  crop  of  legumes 
are  grown  in  three  years. 

A five-year  rotation  of  (1)  corn  (and  clover),  (2)  cowpeas,  (3)  wheat, 
(4)  clover,  and  (5)  wheat  (and  clover)  allows  legumes  to  be  seeded  four 
times,  and  alfalfa  may  be  grown  on  a sixth  field  for  five  or  six  years  in  the 
combination  rotation,  alternating  between  two  fields  every  five  years,  or 
rotating  over  all  fields  if  moved  every  six  years. 

To  avoid  clover  sickness  it  may  sometimes  be  necessary  to  substitute  red 
clover  or  alsike  for  the  other  in  about  every  third  rotation,  and  at  the  same 


36 


Soil  Report  No.  4 


[September, 


time  to  discontinue  their  use  in  the  cover-crop  mixture.  If  the  corn  crop 
is  not  too  rank,  cowpeas  or  soybeans  may  also  be  used  as  a cover  crop  (seeded 
at  the  last  cultivation)  in  the  southern  part  of  the  state,  and,  if  necessary 
to  avoid  disease,  these  may  well  alternate  in  successive  rotations. 

For  easy  figuring  it  may  well  be  kept  in  mind  that  the  following  amounts 
of  nitrogen  are  required  for  the  produce  named : 

1 bushel  of  oats  (grain  and  straw)  requires  1 pound  of  nitrogen. 

1 bushel  of  corn  (grain  and  stalks)  requires  V/2  pounds  of  nitrogen. 

1 bushel  of  wheat  (grain  and  straw)  requires  2 pounds  of  nitrogen. 

1 ton  of  timothy  requires  24  pounds  of  nitrogen. 

1 ton  of  clover  contains  40  pounds  of  nitrogen. 

1 ton  of  cowpeas  contains  43  pounds  of  nitrogen. 

1 ton  of  average  manure  contains  10  pounds  of  nitrogen. 

The  roots  of  clover  contain  about  half  as  much  nitrogen  as  the  tops,  and 
the  roots  of  cowpeas  contain  about  one-tenth  as  much  as  the  tops. 

Soils  of  moderate  productive  power  will  furnish  as  much  nitrogen  to 
clover  (and  two  or  three  times  as  much  to  cowpeas)  as  will  be  left  in  the 
roots  and  stubble.  For  grain  crops,  such  as  wheat,  corn,  and  oats,  about  two- 
thirds  of  the  nitrogen  is  contained  in  the  grain  and  one-third  in  the  straw 
or  stalks.  (See  also  discussion  of  “The  Potassium  Problem,”  on  pages  below.) 

(3)  On  all  lands  deficient  in  phosphorus  (except  on  those  susceptible 
to  serious  erosion  by  surface  washing  or  gullying)  apply  that  element  in 
considerably  larger  amounts  than  are  required  to  meet  the  actual  needs  of 
the  crops  desired  to  be  produced.  The  abundant  information  thus  far  se- 
cured shows  positively  that  fine-ground  natural  rock  phosphate  can  be  used 
successfully  and  very  profitably,  and  clearly  indicates  that  this  material  will 
be  the  most  economical  form  of  phosphorus  to  use  in  all  ordinary  systems 
of  permanent,  profitable  soil  improvement.  The  first  application  may  well 
be  one  ton  per  acre,  and  subsequently  about  one-half  ton  per  acre  every  four 
or  five  years  should  be  applied,  at  least  until  the  phosphorus  content  of  the 
plowed  soil  reaches  2,000  pounds  per  acre,  which  may  require  a total  ap- 
plication of  from  three  to  five  or  six  tons  per  acre  of  raw  phosphate  con- 
taining 123/3  percent  of  the  element  phosphorus. 

Steamed  bone  meal  and  even  acid  phosphate  may  be  used  in  emergencies, 
but  it  should  always  be  kept  in  mind  that  phosphorus  delivered  in  Illinois 
costs  about  3 cents  a pound  in  raw  phosphate  (direct  from  the  mine  in  car- 
load lots),  but  10  cents  a pound  in  steamed  bone  meal,  and  about  12  cents 
a pound  in  acid  phosphate,  both  of  which  cost  too  much  per  ton  to  permit 
their  common  purchase  by  farmers  in  carload  lots,  which  is  not  the  case 
with  limestone  or  raw  phosphate. 

Phosphorus  once  applied  to  the  soil  remains  in  it  until  removed  in  crops, 
unless  carried  away  mechanically  by  soil  erosion.  (The  loss  by  leaching 
is  only  about  ip2  pounds  per  acre  per  annum,  so  that  more  than  150  years 
would  be  required  to,  leach  away  the  phosphorus  applied  in  one  ton  of  raw 
phosphate.) 

The  phosphate  and  limestone  may  be  applied  at  any  time  during  the 
rotation,  but  a good  method  is  to  apply  the  limestone  after  plowing  and 
work  it  into  the  surface  soil  in  preparing  the  seed  bed  for  wheat,  oats,  rye, 
or  barley,  where  clover  is  to  be  seeded ; while  phosphate  is  best  plowed  under 
with  farm  manure, -clover,  or  other  green  manures,  which  serve  to. liberate 
the  phosphorus. 


Sangamon  County 


37 


1912] 


(4)  Until  the  supply  of  decaying  organic  matter  has  been  made  ade- 
quate, on  the  poorer  types  of  upland  timber  and  gray  prairie  soils  some 
temporary  benefit  may  be  derived  from  the  use  of  a soluble  salt  or  mixture 
of  salts,  such  as  kainit,  which  contains  both  potassium  and  magnesium  in 
soluble  form  and  also  some  common  salt  (sodium  chlorid)  . About  600 
pounds  per  acre  of  kainit  applied  and  turned  under  with  the  raw  phosphate 
will  help  to  dissolve  the  phosphorus  as  well  as  to  furnish  available  potas- 
sium and  magnesium,  and  for  a few  years  such  use  of  kainit  will  no  doubt 
be  profitable  on  lands  deficient  in  organic  matter,  but  the  evidence  thus  far 
secured  indicates  that  its  use  is  not  absolutely  necessary  and  that  it  will  not 
be  profitable  after  adequate  provision  is  made  for  decaying  organic  matter, 
since  this  will  necessitate  returning  to  the  soil  either  all  produce  except  the 
grain  (in  grain  farming)  or  the  manure  produced  in  live-stock  farming. 
(Where  hay  or  straw  is  sold,  manure  should  be  bought.) 

On  soils  which  are  subject  to  surface  washings,  including  especially  the 
yellow  silt  loam  of  the  upland  timber  area,  and  to  some  extent  the  yellow- 
gray  silt  loam,  and  other  more  rolling  areas,  the  supply  of  minerals  in  the 
subsurface  and  subsoil  (which  gradually  renew  the  surface  soil)  tends  to 
provide  for  a low-grade  system  of  permanent  agriculture  if  some  use  is  made 
of  legume  plants,  as  in  long  rotations  with  much  pasture,  because  both  the 
minerals  and  nitrogen  are  thus  provided  in  some  amount  almost  permanently ; 
but  where  such  lands  are  farmed  under  such  a system,  not  more  than  two  or 
three  grain  crops  should  be  grown  during  a period  of  ten  or  twelve  years, 
the  land  being  kept  in  pasture  most  of  the  time ; and  where  the  soil  is  acid  a 
liberal  use  of  limestone,  as  top  dressings  if  necessary,  and  occasional  re- 
seeding with  clovers  will  benefit  both  the  pasture  and  indirectly  the  grain 
crops. 

Advantage  oe  Crop  Rotation  and  Permanent  Systems 

It  should  be  noted  that  clover  is  not  likely  to  be  well  infected  with  the 
clover  bacteria  during  the  first  rotation  on  a given  farm  or  field  where  it 
has  not  been  grown  before  within  recent  years;  but  even  a partial  stand  of 
clover  the  first  time  will  probably  provide  a thousand  times  as  many  bac- 
teria for  the  next  clover  crop  as  one  could  afford  to  apply  in  artificial  inocu- 
lation, for  a single  root-tubercle  may  contain  a million  bacteria  developed 
from  one  during  the  season’s  growth. 

This  is  only  one  of  several  advantages  of  the  second  course  of  the  rota- 
tion over  the  first  course.  Thus  the  mere  practice  of  crop  rotation  is  an  ad- 
vantage, especially  in  helping  to  rid  the  land  of  insects  and  foul  grass  and 
weeds.  The  deep-rooting  clover  crop  is  an  advantage  to  subsequent  crops 
because  of  that  characteristic.  The  larger  applications  of  organic  manures 
(made  possible  by  the  larger  crops)  are  a great  advantage;  and  in  systems 
of  permanent  soil  improvement,  such  as  are  here  advised  and  illustrated, 
more  limestone  and  more  phosphorus  are  provided  than  are  needed  for  the 
meager  or  moderate  crops  produced  during  the  first  rotation,  and  conse- 
quently the  crops  in  the  second  rotation  have  the  advantage  of  such  accumu- 
lated residues  (well  incorporated  with  the  plowed  soil)  in  addition  to  the 
regular  applications  made  during  the  second  rotation. 

This  means  that  these  systems  tend  positively  toward  the  making  of 
richer  lands.  The  ultimate  analyses  recorded  in  the  tables  give  the  absolute 
invoice  of  these  Illinois  soils.  They  show  that  most  of  them  are  positively 
deficient  only  in  limestone,  phosphorus,  and  nitrogenous  organic  matter:  and 


38 


Soil  Report  No.  4 


[September, 


the  accumulated  information  from  careful  and  long-continued  investigations 
in  different  parts  of  the  United  States  clearly  establishes  the  fact  that  in  gen- 
eral farming  these  essentials  can  be  supplied  with  greatest  economy  and 
profit  by  the  use  of  ground  natural  limestone,  very  finely  ground  natural 
rock  phosphate,  and  legume  crops  to  be  plowed  under  directly  or  in  farm 
manure.  On  normal  soils  no  other  applications  are  absolutely  necessary, 
but,  as  already  explained,  the  addition  of  some  soluble  salt  in  the  beginning 
of  a system  of  improvement  on  some  of  these  soils  produces  temporary 
benefit,  and  if  some  inexpensive  salt,  such  as  kainit,  is  used,  it  may  produce 
sufficient  increase  to  more  than  pay  the  added  cost. 

The  Potassium  Problem 

As  reported  in  Illinois  Bulletin  123,  where  wheat  has  been  grown  every 
year  for  more  than  half  a century  at  Rothamsted,  England,  exactly  the  same 
increase  was  produced  (5.6  bushels  per  acre),  as  an  average  of  the  first 
24  years,  whether  potassium,  magnesium,  or  sodium  was  applied,  the  rate  of 
application  per  annum  being  200  pounds  of  potassium  sulfate  and  molecular 
equivalents  of  magnesium  sulfate  and  sodium  sulfate.  As  an  average  of 
60  years  (1852  to  1911),  the  yield  of  wheat  has  been  12.7  bushels  on  un- 
treated land,  23.3  bushels  where  86  pounds  of  nitrogen  and  29  pounds  of 
phosphorus  per  acre  per  annum  were  applied;  and,  as  further  additions,  85 
pounds  of  potassium  raised  the  yield  to  31.3  bushels;  52  pounds  of  mag- 
nesium raised  it  to  29.2  bushels ; and  50  pounds  of  sodium  raised  it  to 
29.5  bushels.  Where  potassium  was  applied,  the  average  wheat  crop  re- 
moved 40  pounds  of  that  element  in  the  grain  and  straw,  or  three  times  as 
much  as  would  be  removed  in  the  grain  only  for  such  crops  as  are  suggested 
in  Table  A.  The  Rothamsted  soil  contained  an  abundance  of  limestone,  but  no 
organic  matter  was  provided  except  the  little  in  the  stubble  and  roots  of  the 
wheat  plants. 

On  another  field  at  Rothamsted  the  average  yield  of  barley  for  60  years 
(1852  to  1911)  has  been  14.2  bushels  on  untreated  land,  38.1  bushels  where 
43  pounds  of  nitrogen  and  29  pounds  of  phosphorus  have  been  applied 
per  acre  per  annum ; while  the  further  addition  of  85  pounds  of  potassium, 
19  pounds  of  magnesium,  and  14  pounds  of  sodium  (all  in  sulfates)  raised 
the.  average  yield  to  41.5  bushels,  but,  where  only  70  pounds  of  sodium  were 
applied  in  addition  to  the  nitrogen  and  phosphorus,  the  average  has  been 
43.0  bushels.  Thus,  as  an  average  of  60  years,  the  use  of  sodium  pro- 
duced 1.8  bushels  less  wheat  and  1.5  bushels  more  barley  than  the  use  of 
potassium,  with  both  grain  and  straw  removed  and  no  organic  manures 
returned. 

In  recent  years  the  effect  of  potassium  is  becoming  much  more  marked 
than  that  of  sodium  or  magnesium,  on  the  wheat  crop;  but  this  must  be 
expected  to  occur  in  time  where  no  potassium  is  returned  in  straw  or  manure, 
and  no  provision  made  for  liberating  potassium  from  the  supply  still  re- 
maining in  the  soil.  If  more  than  three-fourths  of  the  potassium  removed 
were  returned  in  the  straw  (see  Table  A),  and  if  the  decomposition  prod- 
ucts of  the  straw  have  power  to  liberate  additional  amounts  of  potassium 
from  the  soil,  the  necessity  of  purchasing  potassium  in  a good  system  of 
farming  on  such  land  is  very  remote. 

While  about  half  the  potassium,  nitrogen,  and  organic  matter,  and 
about  one-fourth  the  phosphorus  contained  in  manure  will  be  lost  bv 
three  or  four  months’  exposure  in  the  ordinary  pile  in  the  barn  yard,  there 


Sangamon  County 


39 


1912] 


is  practically  no  loss  if  plenty  of  absorbent  bedding  is  used  on  cement  floors, 
and  if  the  manure  is  hauled  to  the  field  and  spread  within  a day  or  two 
after  it  is  produced.  Again,  while  the  animals  destroy  two-thirds  of  the 
organic  matter  and  retain  one-fourth  of  the  nitrogen  and  phosphorus  in 
average  live-stock  farming,  they  retain  less  than  one-tenth  of  the  potassium, 
from  the  food  consumed ; so  that  the  actual  loss  of  potassium  in  the  products 
sold  from  the  farm,  either  in  grain  farming  or  in  live-stock  farming,  is 
wholly  negligible  on  land  containing  25,000  pounds  or  more  of  potassium 
in  the  surface  6-/3  inches. 

The  removal  of  one  inch  of  soil  per  century  by  surface  washing  (which 
is  likely  to  occur  wherever  there  is  satisfactory  surface  drainage  and  frequent 
cultivation)  would  permanently  maintain  the  potassium  in  grain  farming 
by  renewal  from  the  subsoil,  provided  one-third  of  the  potassium  is  removed 
by  cropping  before  the  soil  is  carried  away. 

From  all  of  these  facts  it  will  be  seen  that  the  potassium  problem  is  not 
one  of  addition  but  of  liberation;  and  the  Rothamsted  records  show  that 
for  many  years  other  soluble  salts  have  practically  the  same  power  as  po- 
tassium to  increase  crop  yields  in  the  absence  of  sufficient  decaying  organic 
matter.  Whether  this  action  relates  to  supplying  or  liberating  potassium  for 
its  own  sake,  or  to  the  power  of  the  soluble  salt  to  increase  the  availability 
of  phosphorus  or  other  elements,  is  not  known,  but  where  much  potassium 
is  removed,  as  in  the  entire  crops  at  Rothamsted,  with  no  return  of  organic 
residues,  probably  the  soluble  salt  functions  in  both  ways. 

As  an  average  of  112  separate  tests  conducted  in  1907,  1908,  1909,  and 
1910  on  the  Fairfield  experiment  field,  an  application  of  200  pounds  of 
potassium  sulfate,  containing  85  pounds  of  potassium  and  costing  $5.10,  in- 
creased the  yield  of  corn  by  9.3  bushels  per  acre ; while  600  pounds  of  kainit, 
containing  only  60  pounds  of  potassium  and  costing  $4.00,  gave  an  increase 
of  10.7  bushels.  Thus,  at  40  cents  a bushel  for  corn,  the  kainit  has  paid  for 
itself ; but  these  results,  like  those  at  Rothamsted,  were  secured  where  no 
adequate  provision  had  been  made  for  decaying  organic  matter. 

Additional  experiments  at  Fairfield  include  an  equally  complete  test  with 
potassium  sulfate  and  kainit  on  land  to  which  8 tons  per  acre  of  farm 
manure  had  been  applied.  As  an  average  of  112  tests  with  each  material, 
the  200  pounds  of  potassium  sulfate  increased  the  yield  of  corn  by  1.7  bush- 
els, while  the  600  pounds  of  kainit  also  gave  an  increase  of  1.7  bushels. 
Thus,  where  organic  manure  was  supplied,  very  little  effect  was  produced 
by  the  addition  of  either  potassium  sulfate  or  kainit ; in  part  perhaps  because 
the  potassium  removed  in  the  crops  is  mostly  returned  in  the  manure  if 
properly  cared  for;  and  perhaps  in  larger  part  because  the  decaying  organic 
matter  helps  to  liberate  and  hold  in  solution  other  plant-food  elements,  es- 
pecially phosphorus. 

In  laboratory  experiments  at  the  Illinois  Experiment  Station,  it  has  been 
shown  that  potassium  salts  and  most  other  soluble  salts  increase  the  solu- 
bility of  the  phosphorus  in  soil  and  in  rock  phosphate  as  determined  by  chem- 
ical analysis;  also  that  the  addition  of  glucose  with  rock  phosphate  in  pot- 
culture  experiments  increases  the  availability  of  the  phosphorus,  as  measured 
by  plant  growth,  altho  the  glucose  consists  only  of  carbon,  hydrogen,  and 
oxygen,  and  thus  contains  no  plant  food  of  value. 

If  we  remember  that,  as  an  average,  live  stock  destroy  two-thirds  of  the 
organic  matter  of  the  food  consumed,  it  is  easy  to  determine  from  Table  A 


40 


Son-  Report  No.  4 


[September, 


that  more  organic  matter  will  be  supplied  in  a proper  grain  system  than 
in  a strictly  live-stock  system ; and  the  evidence  thus  far  secured  from  older 
experiments  at  the  University  and  at  other  places  in  the  state  indicates  that 
if  the  corn  stalks,  straw,  clover,  etc.,  are  incorporated  with  the  soil  as  soon 
as  practicable  after  they  are  produced  (which  can  usually  be  done  in  the 
late  fall  or  early  spring),  there  is  little  or  no  difficulty  in  securing  sufficient 
decomposition  in  our  humid  climate  to  avoid  serious  interference  with  the 
capillary  movement  of  the  soil  moisture,  a common  danger  from  plowing  un- 
der too  much  coarse  manure  of  any  kind  in  the  late  spring  of  a dry  year. 

If,  however,  the  entire  produce  of  the  land  is  sold  from  the  farm,  as 
in  hay  farming,  or  when  both  grain  and  straw  are  sold,  of  course  the  draft 
on  potassium  will  then  be  so  great  that  in  time  it  must  be  renewed  by  some 
sort  of  application.  As  a rule,  such  farmers  ought  to  secure  manure  from 
town,  since  they  furnish  the  bulk  of  the  material  out  of  which  manure  is 
produced. 

Calcium  and  Magnesium 

When  measured  by  the  actual  crop  requirements  for  plant  food,  mag- 
nesium and  calcium  are  more  limited  in  some  Illinois  soils  than  potassium. 
But  with  these  elements  we  must  also  consider  the  loss  by  leaching.  As  an 
average  of  90  analyses*  of  Illinois  well-waters  drawn  chiefly  from  glacial 
sands,  gravels,  or  till,  3 million  pounds  of  water  (about  the  average  annual 
drainage  per  acre  for  Illinois)  contained  11  pounds  of  potassium,  130  of 
magnesium,  and  330  of  calcium.  These  figures  are  very  significant,  and  it 
may  be  stated  that  if  the  plowed  soil  is  well  supplied  with  the  carbonates  of 
magnesium  and  calcium,  then  a very  considerable  proportion  of  these 
amounts  will  be  leached  from  that  stratum.  Thus  the  loss  of  calcium  from 
the  plowed  soil  of  an  acre  at  Rothamsted,  England,  where  the  soil  contains 
plenty  of  limestone,  has  averaged  more  than  300  pounds  a year  as  determined 
by  analyzing  the  soil  in  1865  and  again  in  T905.  And  practically  the  same 
amount  of  calcium  was  found  by  analyzing  the  Rothamsted  drainage  waters. 

Common  limestone,  which  is  calcium  carbonate  (CaC03),  contains,  when 
pure,  40  percent  of  calcium,  so  that  800  pounds  of  limestone  are  equivalent 
to  320  pounds  of  calcium.  Where  10  tons  per  acre  of  ground  limestone  were 
applied  at  Edgewood,  Illinois,  the  average  annual  loss  during  the  next  ten 
years  amounted  to  790  pounds  per  acre.  The  definite  data  from  careful 
investigations  seems  to  be  ample  to  justify  the  conclusion  that  where  lime- 
stone is  needed  at  least  2 tons  per  acre  should  be  applied  every  4 or  5 years. 

It  is  of  interest  to  note  that  thirty  crops  of  clover  of  four  tons  each 
would  require  3,510  pounds  of  calcium,  while  the  most  common  prairie  land 
of  southern  Illinois  contains  only  3,420  pounds  of  total  calcium  in  the 
plowed  soil  of  an  acre.  (See  Soil  Report  No.  T.)  Thus  limestone  has  a 
positive  value  on  some  soils  for  the  plant  food  which  it  supplies,  in  addition 
to  its  value  in  correcting  soil  acidity  and  in  improving  the  physical  condi- 
tion of  the  soil.  Ordinary  limestone  (abundant  in  the  southern  and  western 
parts  of  the  state)  contains  nearly  800  pounds  of  calcium  per  ton;  while  a 
good  grade  of  dolomitic  limestone  (the  more  common  limestone  of  northern 
Illinois)  contains  about  400  pounds  of  calcium  and  300  pounds  of  mag- 
nesium per  ton.  Both  of  these  elements  are  furnished  in  readily  available 
form  in  ground  dolomitic  limestone. 


*Reported  by  Doctor  Bartow  and  associates,  of  tbe  Illinois  State  Water  Survey. 


UNIVERSITY  OF  ILLINOIS 


Agricultural  Experiment  Station 


SOIL  REPORT  NO.  5 


LA  SALLE  COUNTY  SOILS 


By  CYRIL  G.  HOPKINS,  J.  G.  M09IER, 
J.  H.  PETTIT,  and  J.  E.  READHIMER 


URBANA,  ILLINOIS,  JULY,  1913 


State  Advisory  Committee  on  Sou,  Investigations 

Ralph  Allen,  Delavan 
F.  I.  Mann,  Gilman 
A.  N.  Abbott,  Morrison 
J.  P.  Mason,  Elgin 

C.  V.  Gregory,  538  S.  Clark  St.,  Chicago. 

Agricueturae  Experiment  Station  Staff  on  Soie  Investigations 
Eugene  Davenport,  Director 

Cyril  G.  Hopkins,  Chief  in  Agronomy  and  Chemistry 

Soil  Survey — 

J.  G.  Mosier,  Chief 
A.  F.  Gustafson,  Associate 
S.  V.  Holt,  Associate 
H.  W.  Stewart,  Associate 
H.  C.  Wheeler,  Associate 
F.  A.  Fisher,  Assistant 
F.  M.  W.  Wascher,  Assistant 
R.  W.  Didkenson,  Assistant 
John  Woodard,  Assistant 

Soil  Analysis 

J.  H.  Pettit,  Chief 
E.  Van  Alstine,  Associate 
J.  P.  Aumer,  Associate 
W.  H.  Sachs,  First  Assistant 
Gertrude  Niederman,  Assistant 
W.  R.  Leighty,  Assistant 
Oran  Keller,  Assistant 
L.  R.  Binding,  Assistant 

Soil  Biology 

A.  L.  Whiting*  First  Assistant 

Soil  Experiment  Fields — • 

J.  E.  Readhimer,  Superintendent 
Wm.  G.  Eckhardt,1  Associate 
O.  S.  Fisher,  Associate 
J.  E.  Whitchurch,  Associate 

E.  E.  Hoskins,  Associate 

F.  C.  Bauer,  First  Assistant 
F.  W.  Garrett,  Assistant 


Soils  Extension — 

C.  C.  Logaa,  Associate 


'On  leave. 


^ RKOBTVBD  * 

* SEP  15  1913  *] 


^^UoFrnmM 


LASALLE  COUNTY  SOILS 

BV CYRIL,  G.  HOPKINS,  J.  G.  MOS1ER,  J.  H.  PETTIT,  and  J.  E-  READHIMER 


INTRODUCTION 

About  two-thirds  of  Illinois  lies  in  the  corn  belt,  where  most  of  the 
prairie  lands  are  black  or  dark  brown  in  color.  In  the  southern  third  of 
the  state,  the  prairie  soils  are  largely  of  a gray  color.  This  region  is  better 
known  as  the  wheat  belt,  altho  wheat  is  often  grown  in  the  corn  belt  and 
corn  is  also  a common  crop  in  the  wheat  belt. 

Moultrie  county,  representing  the  corn  belt ; Clay  county,  which  is  fairly 
representative  of  the  wheat  belt ; and  Hardin  county,  which  is  taken  to  rep- 
resent the  unglaciated  area  of  the  extreme  southern  part  of  the  state,  were 
selected  for  the  first  Illinois  Soil  Reports  by  counties.  While  these  three 
county  soil  reports  were  sent  to  the  Station’s  entire  mailing  list  within  the 
state,  Sangamon,  La  Salle,  and  other  subsequent  reports  are  sent  only  to 
the  residents  of  the  county  concerned  and  to  any  one  else  upon  request. 

Each  county  report  is  intended  to  be  as  nearly  complete  in  itself  as  it 
is  practicable  to  make  it,  and,  even  at  the  expense  of  some  repetition,  each 
will  contain  a general  discussion  of  important  fundamental  principles  to  help 
the  farmer  and  landowner  to  understand  the  meaning  of  the  soil  fertility 
invoice  for  the  lands  in  which  he  is  interested.  In  Soil  Report  No.  I,  “Clay 
County  Soils,”  this  discussion  serves  in  part  as  an  introduction,  while  in  this 
and  other  reports  it  will  be  found  in  the  Appendix,  but  if  necessary  it  should 
be  read  and  studied  in  advance  of  the  report  proper. 

La  Salle  county  is  located  in  the  north-central  part  of  the  early  Wiscon- 
sin glaciation.  The  soils  of  the  county /are  divided  into  five  classes  as  fol- 
lows : 

(1)  Upland  prairie  soils,  rich  in  organic  matter.  These  were  originally 
covered  with  wild  prairie  grasses,  the  partially  decayed  roots  of  which  have 
been  the  source  of  the  organic  matter.  The  flat  prairie  land  contains  the 
higher  amount  of  this  constituent  because  it  was  largely  preserved  from 
decay  by  the  presence  of  water. 

(2)  Upland  timber  soils,  including  those  zones  along  stream  courses  over 
which  forests  once  extended.  The  timber  land  contains  much  less  organic 
matter  because  the  large  roots  of  dead  trees  and  the  surface  layer  of  leaves, 
twigs,  and  fallen  trees  were  burned  by  forest  fires  or  suffered  almost  com- 
plete decay. 

(3)  Terrace  soils,  or  second  bottom  land,  representing  the  soils  formed 
on  fills  of  either  silt  or  gravel  or  the  flood  plain  of  a stream  when  it  flowed 
at  a higher  level  than  at  present. 

(4)  Swamp  and  bottom  lands,  which  include  the  lands  that  overflow 
along  streams  and  a few  small  areas  of  swamps  on  the  upland. 


1 


2 


Soil  Report  No.  5 [July, 

(5)  Residual  soils,  formed  by  the  decomposition  of  rocks  in  place.  The 
entire  area  of  this  class  is  only  2^4  square  miles. 

The  general  topography  of  the  county  is  undulating  or  slightly  rolling. 
There  are,  however,  some  very  flat  areas;  also  belts  of  very  rolling  or 
hilly  land  along  the  larger  streams,  and  considerable  areas  of  terraces  and 
bottom  lands.  The  difference  in  topography  is  due  mainly  to  two  causes — 
glacial  action  and  stream  erosion.  Like  most  of  the  state,  this  county  was 
covered  by  a glacial  ice  sheet  during  what  is  known  as  the  glacial  period. 
During  this  time,  snow  and  ice  accumulated  in  the  vicinity  of  Hudson  Bay 
to  such  an  amount  that  it  flowed  southward  until  a point  was  reached  where 
the  ice  melted  as  rapidly  as  it  advanced. 

In  moving  across  the  country,  the  ice  gathered  up  all  sorts  and  sizes  of 
earthy  material,  including  pebbles,  boulders,  and  even  large  masses  of  rock. 
Many  of  these  were  carried  for  hundreds  of  miles  and  rubbed  against  the 
surface  rocks  or  against  each  other  until  ground  into  powder.  When  the 
limit  of  advance  was  reached,  where  the  ice  largely  melted,  all  of  this  mate- 
rial would  accumulate  in  a broad,  undulating  ridge,  or  moraine.  When  the  ice 
melted  away  more  rapidy  than  it  advanced,  the  terminus  of  the  glacier  would 
recede  and  leave  a moraine  of  boulder  clay  to  mark  the  outer  limit  of  the 
ice  sheet. 

The  ice  made  many  advances,  and  with  each  advance  a terminal  moraine 
was  formed.  This  has  left  a system  of  terminal  moraines  (irregularly  con- 
centric with  Lake  Michigan)  having  generally  a steep  outer  slope  while  the 
inner  slope  is  vertically  much  less  but  longer  and  more  gradual.  The  inter- 
morainal  tracts  are  occupied  chiefly  by  the  broad  areas  of  level  or  undulating 
prairies. 

The  material  transported  by  the  glacier  varied  with  the  character  of  the 
rocks  over  which  it  passed.  Granites,  limestones,  sandstones,  shales,  etc., 
were  mixed  and  ground  up  together.  This  mixture  of  all  kinds  of  boulders, 
gravel,  sand,  silt,  and  Clay  is  called  boulder  clay,  till,  glacial  draft,  or  simply 
drift.  The  grinding  and  denuding  power  of  glaciers  is  enormous.  A mass 
of  ice  100  feet  thick  exerts  a pressure  of  40  pounds  per  square  inch,  and  this 
ice  sheet  may  have  been  thousands  of  feet  in  thickness. 

The  materials  pushed  along  in  this  mass  of  ice,  especially  the  boulders 
and  pebbles,  became  powerful  agents  for  grinding  and  wearing  away  the 
surface  over  which  the  ice  passed.  Ridges  and  hills  were  rubbed  down  and 
valleys  filled,  and  the  surface  features  changed  entirely. 

A deposit  of  boulder  clay  covered  the  entire  upland  of  the  county  to  a 
depth  varying  from  5 to  300  feet,  with  an  average  of  about  100  feet;  but 
this  was  later  covered  by  a deposit  of  loess,  as  hereinafter  explained. 

Physiography 

The  altitude  of  La  Salle  county  varies  from  430  feet  in  the  Illinois-river 
valley  to  930  feet  on  the  Bloomington  moraine  north  of  Mendota.  Other 
high  altitudes  are  in  the  southwest  and  southeast  parts  of  the  county,  but 
about  four-fifths  of  the  entire  county  is  less  than  700  feet  above  sea  level. 

The  valley  of  the  Illinois  river  is  from  200  to  300  feet  below  the  gen- 
eral upland.  This  has  permitted  considerable  erosion,  and  as  a result  the 
land  adjacent  to  the  bottom  land  of  the  larger  streams  is  cut  up  into  hills 
and  valleys  unsuited  for  ordinary  agriculture.  Before  the  land  was  put  un- 


La  Salle  County 


3 


1913] 

der  cultivation,  forests  had  extended  their  way  up  the  smaller  streams  and 
were  slowly  invading  the  adjoining  prairies.  The  influence  of  the  prevail- 
ing southwesterly  wind  may  be  seen  in  the  greater  extension  of  the  forests 
to  the  north  and  east  of  the  protecting  streams,  as  shown  in  the  soil  types. 

The  early  Wisconsin  glacier  is  responsible  for  three  moraines:  one,  a 
very  distinct  ridge,  known  as  the  Bloomington  moraine,  crosses  the  north- 
west corner  of  the  county ; another,  less  distinct,  crosses  the  Illinois  river 
at  Utica  and  extends  northeast  and  southeast  from  this  point,  the  north  arm 
terminating  near  Earlville  and  the  south  arm  coalescing  with  another  moraine 
in  the  southeast  part  of  the  county;  the  third,  the  Marseilles  moraine,  enters 
the  county  northeast  of  the  town  of  Marseilles,  extends  southwest  across  the 
Illinois  river  and  thence  southward  into  Livingston  county.  Between  these 
moraines  are  broad  inter-morainal  areas  of  gently  rolling  prairie  land  with 
many  flat  areas  of  poor  drainage.  The  old  drainage  system  was  almost  com- 
pletely filled  and  destroyed  by  the  glacial  drift,  but  gradually  a new  system 
has  been  developed.  The  large  streams  have  eroded  valleys  from  5 to  250  feet 
deep  and  in  some  cases  have  formed  narrow  flood  plains.  Small  streams 
tributary  to  the  large  ones  have  formed  valleys  extending  back  from  the  bluffs, 
and  along  the  larger  streams  there  gradually  has  been  formed  a zone  of  broken 
to  hilly  land.  The  time  elapsed  since  the  glaciers,  however,  has  not  been  suf- 
ficient to  develop  a complete  natural  drainage  system  for  the  county,  and  it 
therefore  has  been  necessary  to  supplement  the  work  of  nature  by  artificial 
means,  with  the  result  that  the  entire  upland  of  the  county  is  now  well 
drained.  The  Illinois  river  flowing  thru  the  central  part  of  the  county  from 
east  to  west  furnishes  a good  outlet  for  the  half  dozen  streams  with  their 
tributaries  that  drain  the  county. 

Bench  lands,  or  terraces,  are  found  along  the  larger  streams;  namely, 
the  Illinois,  Fox,  and  Vermilion  rivers,  and  Indian  creek, — a fact  which 
indicates  that  these  streams  formerly  carried  a larger  volume  of  both  sedi- 
ment and  water. 

Topography  and  Formation 

The  topography  of  the  bottom  lands  is  modified  somewhat  by  deforma- 
tion. All  limestones,  sandstones,  and  shales  were  formed  in  large  bodies 
of  water,  from  material  deposited  in  almost  horizontal  strata.  Usually 
when  this  became  dry  land,  the  strata  still  remained  horizontal.  Sometimes 
long  fissures  would  occur  in  these  rocks  and  one  side  would  push  up  or  drop 
down  so  that  the  rocks  on  the  opposite  sides  would  not  correspond.  This 
formation  is  called  a fault.  Sometimes  the  strata  of  rock  would  be  pushed 
up  into  arches,  or  even  into  folds,  as  the  earth  contracted,  forming  what  are 
known  as  anticlines. 

The  La  Salle  anticline  (arch)  has  a steep  slope  to  the  southwest,  while 
the  slope  to  the  northeast  is  more  gradual.  This  anticline  enters  the  state 
from  Wisconsin  near  Winslow  (Stephenson  county),  passes  near  Grand 
Detour,  La  Salle,  Tuscola,  and  Bridgeport  (Lawrence  county),  and  is  re- 
sponsible for  the  oil  fields  (which  lie  beneath  the  arch)  in  the  southeastern 
part  of  the  state.  This  anticline  does  not  seem  to  affect  the  topography  of 
the  upland  in  La  Salle  county,  but  in  the  valley  of  the  Illinois  river  its  effect 
is  very  striking.  West  of  the  anticline  the  bottom  land  all  overflows,  and 
is  what  is  commonly  called  first  bottom;  while  east  of  the  anticline  the  over- 
flow land  is  of  small  extent  and  in  many  places  is  either  entirely  absent  or 
is  replaced  by  second  bottom,  or  bench  lands.  Most  of  these  lands  are  un- 


4 


Soil  Report  No.  5 


[July, 


derlain  by  rock  at  no  great  depth;  in  fact,  the  rock  frequently  comes  too 
near  to  the  surface  to  permit  tillage.  The  underlying  rock  is  mostly  sand- 
stone. In  some  cases  it  even  gives  rise  to  a residual  soil  type  (No.  060.5), 
and  it  also  modifies  the  more  common  brown  sandy  loam  on  rock  (No. 
1560.5). 


Soil,  Material,  and  Sou,  Types 

The  early  Wisconsin  glacier  covered  La  Salle  county  and  left  a thick 
mantle  of  drift,  completely  burying  the  old  soil  that  preceded  it.  Later 
other  ice  invasions  of  Illinois  occurred,  but  they  covered  only  the  north- 
eastern part  of  the  state.  (See  state  map  in  Bulletin  123,  late  Wisconsin 
glaciation.)  These  ice  sheets  did  not  reach'La  Salle  county,  but  finely  ground 
rock  (rock  flour)  in  immense  quantities  was  carried  south  by  the  waters 
from  the  melting  ice  and  deposited  on  the  flooded  plains,  where  it  was  picked 
Table  1.— Soil  Types  oe  La  Salle  County 


Soil 

type 

No. 

Name  of  types 

Area  in 
square 
miles 

Area 

in 

acres 

Percent 

of 

total  area 

(a)  Upland  Prairie  Soils  (page  20) 

926  | 
1126  \ 

Brown  silt  loam 

922.16 

590182.4 

79.7143 

1120 

Black  clay  loam 

6.40 

4096.0 

.5532 

1125 

Black  silt  loam 

17.39 

11129.6 

1.5032 

1160 

Brown  sandy  loam 

.02 

12.8 

.0017 

(b)  Upland  Timber  Soils  (page  23) 

934  l 
1134  f 

Yellow-gray  silt  loam 

94.56 

60518.4 

8.1741 

935  ) 
1135  1 

Yellow  silt  loam  

41.12 

26316.8 

3.5545 

1199 

Rock  outcrop 

2.40 

1536.0 

.2074 

(c)  Terrace  Soils  (page  27) 

1526 

Brown  silt  loam  

10.76 

6566.4 

.8869 

1526.4 

Brown  silt  loam  on  gravel2  

.13 

83.2 

.0112 

1526.5 

Brown  silt  loam  on  rock 

.06 

38.4 

.0052 

1527 

Brown  silt  loam  over  gravel2 

5.12 

3276.8 

.4426 

1534.4 

Yellow-grav  silt  loam  on  gravel 

.02 

12.8 

.0017 

1536 

Yellow-gray  silt  loam  over  gravel  

6.68 

4275.2 

.5774 

1560 

Brown  sandy  loam' 

4.80 

3072.0 

.4157 

1560.4 

Brown  sandy  loam  on  gravel 

.30 

192.0 

.0259 

1560.5 

Brown  sandy  loam  on  rock 

5.73 

3667.2 

.4953 

1564 

Yellow-gray  sandy  loam 

.01 

6.4 

.0008 

1581 

Dune  sand..  

.0* 

25.6 

.0034 

1590 

Gravelly  loam 

.47 

300.8 

.0406 

(d)  Swamp  and  Bottom-Land  Soils  (page  31) 

1401 

Deep  peat  

.57 

364.8 

.0192 

1402 

Medium  peat  on  clay 

.13 

83.2 

.0112 

1426 

Deep  brown  silt  loam.. 

11.48 

7347.2 

.9923 

1454 

Mixed  loam  

16.76 

10726.4 

1.4487 

(e)  Residual  Soils  (page  33) 

060.5 

Brown  sandy  loam  on  rock 

2.38 

1523.2 

.2057 

083  . 

Residual  sand  ... 

.11 

70.4 

.0095 

(f)  Miscellaneous 

Shale  pits  

.54 

345.6 

.0467 

River 

7.19 

4601.6 

.6216 

'See  map  and  text  for  area. 

2“On”  signifies  that  the  gravel  or  rock  is  less  than  30  inches  below  tl$e  surface; 
“over,”  more  than  30  inches. 


DEKALB  R.  3 E.  COUNTY 


La  Salle  County 


5 


1913] 

up  by  the  wind,  carried  forward,  and  deposited  upon  the  surface,  burying 
the  drift  material  of  the  early  Wisconsin  glaciation  to  a depth  of  2 to  10 
feet  or  morL  This  wind-blown  material,  called  loess,  represents  a mixture 
of  all  kinds  of  material  over  which  the  glacier  passed. 

After  the  loessial  material  was  deposited  over  the  surface  of  the  country, 
vegetation  developed,  and  organic  matter  became  incorporated  with  the  loess 
to  a greater  or  less  extent,  thus  gradually  changing  it  into  normal  soil.  Sur- 
face washing  has  made  additional  modifications. 

Table  1 shows  the  area  of  each  type  of  soil  in  the  county  and  its  per- 
centage of  the  total  area. 

It  will  be  noted  that  four-fifths  of  the  entire  county  is  covered  with  the 
common  prairie  soil,  known  as  brown  silt  loam,  while  the  black  silt  loam 
and  black  clay  loam  (sometimes  called  “black  gumbo”),  occupying  the  flat 
upland  prairie,  aggregate  only  2 percent. 

About  8 percent  of  the  county  consists  of  yellow-gray  silt  loam,  the  un- 
dulating upland  soil  once  covered  with  timber.  The  more  rolling  yellow 
silt  loam,  also  timber  upland,  is  nearly  half  as  extensive. 

The  terrace  types  cover  3 percent  of  the  area  of  the  county  and  the  bot- 
tom lands  and  rivers  also  about  3 percent. 

The  accompanying  maps  show  the  location  and  boundary  lines  of  every 
type  of  soil  in  the  county,  even  down  to  areas  of  a few  acres;  and  in  Table 
2 are  reported  the  amounts  of  organic  carbon  (the  best  measure  of  the  or- 
ganic matter)  and  the  total  amounts  of  the  five  important  elements  of  plant 
food  contained  in  2 million  pounds  of  the  surface  soil  of  each  type  (the 
plowed  soil  of  an  acre  about  6^3  inches  deep).  In  addition,  the  table  shows 
the  amount  of  limestone  present,  if.  any,  or  the  amount  of  limestone  required 
to  neutralize  the  acidity  existing  in  the  soil.1 

THE  INVOICE  AND  INCREASE  OF  FERTILITY  IN  LA  SALLE 
COUNTY  SOILS 

Soil  Analysis 

In  order  to  avoid  confusion  in  applying  in  a practical  way  the  technical 
information  contained  in  this  report,  the  results  are  given  in  the  most  simpli- 
fied form.  The  composition  reported  for  a given  soil  type  is,  as  a rule,  the 
average  of  many  analyses,  which,  like  most  things  in  nature,  show  more  or 
less  variation ; but  for  all  practical  purposes  the  average  is  most  trustworthy 
and  sufficient.  (See  Bulletin  123,  which  reports  the  general  soil  survey  of 
the  state,  together,  with  many  hundred  individual  analyses  of  soil  samples 
representing  twenty-five  'of  the  most  important  and  most  extensive  soil  types 
in  the  state.) 


’The  figures  given  in  Table  2 (and  in  the  corresponding  tables  for  subsurface  and 
subsoil)  are  the  averages  for  all  determinations  made,  with  the  exception  of  the  acidity 
or  the  limestone  present  in  two  soil  types.  As  a rule,  the  brown  silt  loam  is  slightly 
acid  in  the  surface  and  subsurface,  and  sometimes  the  acidity  extends  to  the  subsoil, 
but  where  samples  were  taken  from  the  heavier  phase  of  this  type  (near  old  draws  or 
perhaps  near  the  shore  lines  of  what  may  once  have  been  ponds)  an  abundance  of  lime 
carbonate  was  usually  found  in  the  subsoil  and,  in  a few  cases,  even  in  the  surface  and 
subsurface,  as  is  shown  in  the  tables.  The  other  exception  occurred  with  one  sample  of 
subsoil  of  the  yellow-gray  silt  loam,  which  showed  the  presence  of  limestone,  but  this 
stratum,  as  well  as  the  surface  and  subsoil,  is  usually  acid,  and  consequently  this 
exceptional  result  was  not  included  in  the  average. 


Soil  Report  No.  5 


[July, 


The  chemical  analysis  of  the  soil  gives  the  invoice  of  fertility  actually 
present  in  the  soil  strata  sampled  and  analyzed,  but,  as  explained  in  the  Ap- 
pendix, the  rate  of  liberation  is  governed  by  many  factors.  Also,  as  there 
stated,  probably  no  agricultural  fact  is  more  generally  known  by  farmers  and 
landowners  than  that  soils  differ  in  productive  power.  Even  tho  plowed  alike 
and  at  the  same  time,  prepared  the  same  way,  planted  the  same  day  with 
the  same  kind  of  seed,  and  cultivated  alike,  watered  by  the  same  rains  and 
warmed  by  the  same  sun,  nevertheless  the  best  acre  may  produce  twice  as 
large  a crop  as  the  poorest  acre  on  the  same  farm,  if  not,  indeed,  in  the  same 
field;  and  the  fact  should  be  repeated  and  emphasized  that  the  productive 
power  of  normal  soil  in  humid  sections  depends  upon  the  stock  of  plant  food 
contained  in  the  soil  and  upon  the  rate  at  which  it  is  liberated. 

The  fact  may  be  repeated,  too,  that  crops  are  not  made  out  of  nothing. 
They  are  composed  of  ten  different  elements  of  plant  food,  every  one  of 
which  is  absolutely  essential  for  the  growth  and  formation  of  every  agri- 
cultural plant.  Of  these  ten  elements  of  plant  food,  only  two  (carbon  and 
oxygen)  are  secured  from  the  air  by  all  plants,  only  one  (hydrogen)  from 
water,  while  seven  are  secured  from  the  soil.  Nitrogen,  one  of  these 
seven  elements  secured  from  the  soil  by  all  plants,  may  also  be  secured  from 
the  air  by  one  class  of  plants  (legumes)  in  case  the  amount  liberated  from 
the  soil  is  insufficient.  But  even  the  leguminous  plants  (which  include  the 
clovers,  peas,  beans,  alfalfa,  and  vetches),  in  common  with  other  agricultural 
plants,  secure  from  the  soil  alone  six  elements  (phosphorus,  potassium,  mag- 
nesium, calcium,  iron,  and  sulfur)  and  also  utilize  the  soil  nitrogen  so  far 
as  it  becomes  soluble  and  available  during  their  period  of  growth. 

Table  A in  the  Appendix  shows  the  requirements  of  large  crops  for  the 
five  most  important  plant-food  elements  which  the  soil  must  furnish.  (Iron 
and  sulfur  are  supplied  normally  from  natural  sources  in  sufficient  abundance, 
compared  with  the  amounts  needed  by  plants,  so  that  they  are  never  known 
to  limit  the  yield  of  common  farm  crops.) 

As  stated,  the  data  in  Table  2 represent  the  total  amounts  of  plant-food 
elements  found  in  2 million  pounds  of  surface  soil,1  which  corresponds  to  an 
acre  about  6 2/j,  inches  deep.  This  includes  at  least  as  much  soil  as  is  ordi- 
narily turned  with  the  plow,  and  represents  that  part  with  which  the  farm 
manure,  limestone,  phosphate,  or  other  fertilizer  applied  in  soil  improve- 
ment is  incorporated.  It  is  the  soil  stratum  that  must  be  depended  upon 
in  large  part  to  furnish  the  necessary  plant  food  for  the  production  of 
crops,  as  will  be  seen  from  the  information  given  in  the  Appendix.  Even 
a rich  subsoil  has  little  or  no  value  if  it  lies  beneath  a worn-out  surface,  but 
if  the  fertility  of  the  surface  soil  is  maintained  at  a high  point,  then  the  strong, 
vigorous  plants  will  have  power  to  secure  more  plant  food  from  the  sub- 
surface and  subsoil  than  would  weak,  shallow-rooted  plants. 

By  easy  computation  it  will  be  found  that  the  most  common  prairie  soil 
of  La  Salle  county  does  not  contain  more  than  enough  total  nitrogen  in  the 
plowed  soil  for  the  production  of  maximum  crops  for  twelve  rotations;  while 
the  upland  timber  soils  contain,  as  an  average,  less  than  one-half  as  much 
nitrogen  as  the  prairie  land. 

1In  all  strata  the  weight  of  peat  is  figured  at  l/z  and  that  of  sand  at  the  weight 

of  normal  soils. 


i 


SOIL  SURVEY  MAP  OF  LASALLE  COUNTY 
UNIVERSITY  OF  ILLINOIS  AGRICULTURAL  EXPERIMENT  STATION 


La  Salle  County 


7 


W3] 


Table  2.— Fertility  in  the  Soils  oe  La  Salle  County,  Illinois 
Average  pounds  per  acre  in  2 million  pounds  of  surface  soil  (about  0 to  6%  inches) 


Soil 

Total 

Total 

Total 

Total 

Total 

Total 

Lime- 

Lime- 

type 

Soil  type 

organic 

nitro- 

phos- 

potas- 

magne- 

cal- 

stone 

stone 

No. 

carbon 

gen 

phorus 

sium 

sium 

cium 

present 

requir’d 

Upland  Prairie  Soils 


1126 

Brown  silt  loam 

71390 

6102 

1384 

33474 

9567 

15158 

rarely 

often 

1126.3 

Brown  silt  loam 

on  till 

42200 

4360 

1180 

38520 

11200 

8420 

40 

1120 

Black  clay  loam 

81460 

7020 

1780 

36440 

13480 

20300 

1960 

1125 

Black  silt  loam. 

74660 

6850 

1970 

34980 

13380 

21270 

14850 

1160 

Brown  sandy 

loam 

33100 

2820 

1160 

28720 

5480 

7400 

40 

Upland  Timber  Soils 


1134 

Yellow-gray  silt 

loam 

32673 

2527 

1033 

38580 

7053 

8227 

87 

1135 

Y ellow  silt  loam 

23967 

2093 

773 

39033 

7560 

7100 

200 

Terrace  Soils 


1526 

Brown  silt  loam 

65520 

5720 

1860 

56260 

16667 

12000 

2620 

1526.4 

Brown  silt  loam 

on  gravel.  -- 

42760 

3880 

1100 

33740 

7120 

8720 

40 

1526.5 

Brown  silt  loam 

on  rock 

135800 

11460 

4900 

46380 

14680 

21880 

2780 

1527 

Brown  silt  loam 

over  gravel. . . 

40440 

3700 

1020 

35680 

7940 

8920 

60 

1534.4 

Y ellow-gray  silt 

loam  on  gravel 

29120 

2740 

980 

35560 

6280 

9020 

40 

1536 

Yellow-gray  silt 

loam  over 
gravel 

29080 

2700 

980 

37900 

6500 

8380 

60 

1560 

Brown  sandy 

loam 

29240 

2480 

1210 

19110 

3560 

5450 

80 

1560.4 

Brown  sandy 

loam  on  gravel 

25700 

2260 

1360 

25980 

4760 

4740 

80 

1560.5 

Brown  sandy 

loam  on  rock. . 

52780 

5000 

1240 

13120 

5840 

11920 

9900 

1564 

Yellow-  gray 

sandy  loam 
over  gravel. . 

19120 

1560 

740 

30480 

4600 

8980 

4300 

1581 

Dune  sand  

13500 

1300 

780 

23530 

4000 

5880 

80 

1590 

Gravelly  loam. . 

64560 

5960 

1920 

25580 

11220 

17420 

11460 

Swamp  and  Bottom-Land  Soils 


1426 

Deep  brown  silt 
loam 

52460 

4440 

2020 

37960 

30000 

62760 

209500 

1454 

Mixed  loam 
(small  streams) 

42740 

4440 

1260 

33500 

27420 

46880 

161900 

1401 

Deep  peat 

177540 

16080 

1310 

8210 

8370 

129900 

285850 

1402 

Medium  peat 
on  clay 

212320 

19600 

970 

10730 

5140 

16270 

Residual  Soils 


060.5 

Brown  sandy 

loam  on  rock . . 

26400 

2220 

880 

25880 

4480 

1800 

20 

083 

Residual  sand. . 

16380 

850 

700 

7900 

2530 

2650 

4530 

With  respect  to  phosphorus,  the  condition  differs  only  in  degree,  nine- 
tenths  of  the  soil  area  of  the  county  containing  no  more  of  that  element 
than  would  be  required  for  eighteen  crop  rotations  if  such  crop  yields  were 
secured  as  are  suggested  in  Table  A of  the  Appendix.  In  the  case  of  the 


Soil  Report  No.  5 


[ July, 


cereals  it  will  be  seen  from  the  same  table  that  about  three-fourths  of  the 
phosphorus  taken  from  the  soil  is  deposited  in  the  grain,  while  only  one- 
fourth  remains  in  the  straw  or  stalks. 

On  the  other  hand,  the  potassium  is  sufficient  for  25  centuries  if  only  the 
grain  is  sold,  or  for  400  years  even  if  the  total  crops  should  be  removed  and 
nothing  returned.  The  corresponding  figures  are  about  2500  and  600  years 
for  magnesium,  and  about  15,000  and  350  years  for  calcium. 

Thus,  when  measured  by  the  actual  crop  requirements  for  plant  food, 
potassium  is  no  more  limited  than  magnesium  and  calcium,  and,  as  explained 
in  the  Appendix,  with  these  elements  we  must  also  consider  the  heavier  loss 
by  leaching. 

These  general  statements  relating  to  the  total  quantities  of  plant  food 
in  the  plowed  soil  certainly  emphasize  the  fact  that  the  supplies  of  some  of 
these  necessary  elements  of  fertility  are  extremely  limited  when  measured 
by  the  needs  of  large  crop  yields  for  even  one  or  two  generations  of  people. 

The  variation  among  the  different  soil  types  with  respect  to  their  content 
of  important  plant-food  elements  is  also  very  marked.  Thus,  the  prairie 
soils  contain  from  two  to  three  times  as  much  nitrogen  as  the  timber  lands 
of  the  same  topography;  and  the  richest  prairie  land  contains  twice  as  much 
phosphorus  as  the  common  upland  timber  soils. 

On  the  other  hand,  the  most  significant  fact  revealed  by  the  investiga- 
tion of  the  La  Salle  county  soils  is  the  low  phosphorus  content  of  the  com- 
mon brown  silt  loam  prairie,  a type  of  soil  which  covers  more  than  three- 
fourths  of  the  entire  county.  The  market  value  of  this  land  is  about  $200 
an  acre,  and  yet  an  application  of  forty  dollars’  worth  of  fine-ground  raw 
rock  phosphate  would  double  the  phosphorus  content  of  the  plowed  soil,  and, 
if  properly  made,  would  in  the  near  future  double  the  yield  of  clover 
on  the  normal  and  lighter  phases.  If  the  clover  was  then  returned  to  the 
soil,  either  directly  or  in  farm  manure,  the  combined  effect  of  phosphorus 
and  increased  nitrogenous  organic  matter,  with  a good  rotation  of  crops, 
would  in  time  double  the  yield  of  corn  on  most  farms. 

With  6,000  pounds  of  nitrogen  in  the  soil  and  an  inexhaustible  supply  in 
the  air,  with  34,000  pounds  of  potassium  in  the  same  soil  and  with  practi- 
cally no  acidity,  the  economic  loss  in  farming  such  land  with  only  1300 
pounds  of  total  phosphorus  in  the  plowed  soil  can  be  anpreciated  only  by 
the  man  who  fully  realizes  that  the  crop  yields  could  ultimately  be  doubled 
by  adding  phosphorus, — without  change  of  seed  or  season  and  with  very 
little  more  work  than  is  now  devoted  to  the  fields. 

Fortunately,  some  definite  field  experiments  have  already  been  conducted 
on  this  most  extensive  type  of  soil,  not  in  La  Salle  county,  but  on  similar 
soil  in  several  other  counties,  as  at  Urbana  in  Champaign  county,  at  Sibley 
in  Ford  county,  and  at  Bloomington  in  McLean  county. 

Results  or  Field  Experiments  at  Urbana 

A three-year  rotation  of  corn,  oats,  and  clover  was  begun  on  the  North 
Farm  at  the  University  of  Illinois  in  1902,  on  three  fields  of  typical  brown 
silt  loam  prairie  land  which,  after  twenty  years  or  more  of  pasturing,  had 
grown  corn  in  180^,  1896,  and  1897  (when  careful  records  were  kept  of 
the  yields  produced)  and  had  then  been  cropped  with  clover  and  grass  on 
one  field,  oats  on  another,  and  oats,  cowpeas,  and  corn  on  the  third  field, 
until  1901. 


R.4  E.  DEKALB  COUNTY 


& 


H ^ z 

GRUNDY  C OUNTY 


S £ 

o s 


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£ 


SOIL  SUJRVEY  MAP  OF  LASALLE  COUNTY  9°°  °ana 

UNIVERSITY  OF  ILLINOIS  AGRICULTURAL  EXPERIMENT  STATION 


La  Salle  County 


9 


1913] 


As  an  average  of  the  first  three  years  (1902-1904)  phosphorus  increased 
the  crop  yields  per  acre  by  .68  ton  of  clover,  8.8  bushels  of  corn,  and  1.9 
bushels  of  oats. 

During  the  second  three  years  ( 1905-1907)  it  produced  average  increases 
of  .79  ton  of  clover,  13.2  bushels  of  corn,  and  11.9  bushels  of  oats. 

During  the  third  course  of  the  rotation  (1908-1910)  it  produced  average 
increases  of  1.05  tons  of  clover,  18.7  bushels  of  corn,  and  8.4  bushels  of  oats. 

For  convenient  reference  the  results  are  summarized  in  Table  3 (page  10). 

Wheat  is  grown  on  the  University  South  Farm  in  a rotation  experiment 
started  more  recently.  As  an  average  of  the  four  years  1908  to  1911,  raw 


Plate  1.  Wheat  in  1911  on  Urbana  Field 
Cover  Crops  and  Crop  Residues  Plowed  Under 
Average  Yield,  35.2  Bushels  Per  Acre 


10 


Soil  Report  No.  5 


[July, 


Table  3. — Defect  oe  Phosphorus  on  Brown  Silt  Loam  at  Urbana 
(Average  increase  per  acre) 


Rotation 

Years 

Corn, 

bu. 

Oats, 

bu. 

Clover, 

tons 

Value  of 
increase 

Cost  of 
treatment1 

First 

1902,-3,-4 

8.8 

1.9 

.68 

S 7.73 

$7.50 

Second  

1905,-6,-7 

13.2 

11.9 

.79 

12.93 

7.50 

Third 

1908,-9,-10 

18.7 

8.4 

1.05 

15.37 

7.17 

'Prices  used  are  35  cents  a bushel  for  corn,  30  cents  for  oats,  $6  a ton  for  clover 
hay,  10  and  3 cents  a pound,  respectively,  for  phosphorus  in  bone  meal  and  in  rock 
phosphate. 


rock  phosphate  (with  no  previous  application  of  bone  meal)  increased  the 
yield  of  wheat  by  10.3  bushels  per  acre.  Here  too,  as  an  average  of  the  four 
years,  the  phosphorus  applied  paid  back  about  twice  its  cost. 


Plate  2.  Wheat  in  1911  on  Urbana  Field 
Cover  Crops  and  Crop  Residues  Plowed  Under 
Fine-Ground  Rock  Phosphate  Applied 
Average  Yield,  50.1  Bushels  Per  Acre 


H (0  Z 


L,  IVIN  GST  ON  COUNTY 


^^EEIX][I]ED[3DEEII][3I1HCE 


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WOODFORD  COUNTY 

SOIL  SURVEY  MAP  OF^ASALLE  COUNTY 
UNIVERSITY  OF  ILLINOIS  AGRICULTURAL  EXPERIMENT  STATION 


La  Salle  County 


11 


1913 ] 

Wheat  has  also  been  grown  on  the  North  Farm  during  the  last  two  years, 
and  the  average  increase  produced  by  phosphorus  (part  in  bone  meal  and 
part  in  raw  phosphate)  has  been  11  bushels  per  acre. 

In  the  grain  system  of  farming,  the  yield  of  wheat  in  1911  was  35.2 
bushels  per  acre  where  cover  crops  and  crop  residues  are  plowed  under  with- 
out the  use  of  phosphorus;  but  where  rock  phosphate  is  used  the  average 
yield  was  50.1  bushels.  (See  Plates  1 and  2.) 

In  the  live-stock  system,  the  yield  of  wheat  in  1911  was  34.2  bushels 
where  manure  and  cover  crops  are  used  without  phosphate,  and  51.8  bushels, 
as  an  average,  where  rock  phosphate  is  used  in  addition.  (See  Plates  3 
and  4.) 

These  results  emphasize  the  cumulative  effect  of  permanent  systems  of 
soil  improvement. 


Plate  3.  Wheat  in  1911  on  Urbana  Field 
Cover  Crops  and  Farm  Manure  Plowed  Under 
Average  Yield,  34.2  Bushels  Per  Acre 


12 


[July, 


Soil  Report  No.  5 

Results  of  Experiments  on  Sibley  Field 

Tabic  4 gives  the  results  obtained  during  the  past  eleven  years  from  the 
Sibley  soil  experiment  field  located  in  Ford  county  on  typical  brown  silt 
loam  prairie  of  the  Illinois  corn  belt. 

Previous  to  1902  this  land  had  been  cropped  with  corn  and  oats  for  many 
years  under  a system  of  tenant  farming,  and  the  soil  had  become  somewhat 
deficient  in  active  organic  matter.  While  phosphorus  was  the  limiting  ele- 
ment of  plant  food,  the  supply  of  nitrogen  becoming  available  annually  was 
but  little  in  excess  of  the  phosphorus,  as  is  well  shown  by  the  corn  yields 
for  1903,  when  phosphorus  produced  an  increase  of  8 bushels,  nitrogen 
without  phosphorus  produced  no  increase,  but  nitrogen  and  phosphorus  to- 
gether increased  the  yield -by  15  bushels. 

After  six  years  of  additional  cropping,  however,  nitrogen  appears  to  have 
become  the  most  limiting  element,  the  increase  in  the  corn  in  1907  having 


Plate  4.  Wheat  in  1911  on  Urbana  Field 
Cover  Crops  and  Farm  Manure  Plowed  Under 
Fine-ground  Rock  Phosphate  Applied 
Average  Yield,  Si. 8 Bushels  Per  Acre 


La  Salle  Coumy 


13 


Table  4. — Chop  Yields  in  Soil  Experiments,  Sibley  Field 


Brown  silt  loam  prairie; 
early  Wisconsin  glaci- 
ation 

Corn 

1902 

Corn 

1903 

Oats 

19J4 

Wheat 

1905 

Corn 

1906 

Corn 

1907 

Oats 

1908 

Wheat 

1909 

Corn 

1910 

Corn 

1911 

Oats 

1912 

Plot 

Soil  treatment 
applied 

Bushels  per  acre 

101 

None 

57.3 

50.4 

'4  4 

29.5 

36.7 

33.9 

25.9 

25.3 

26.6 

20.7 

84.4 

102 

Lime 

60.0 

54. ( 

'74.7 

31.7 

39.2 

38.9 

24.7 

28.8 

34  0 

22.2 

85.6 

103 

Lime,  nitrogen  . . 

60.0 

54.3 

77.5 

32.8 

41.7 

48  1 

1 36.3 

19.0 

29.0 

22.4 

25.3 

104 

Lime,  phosphorus 

61.3 

62.3 

92.5 

36.3 

44.8 

43.5 

25.6 

32.2 

52.0 

31.6 

92.3 

103 

Eime,  potassium. 

56.0 

49.9 

74.4 

30.2 

37.5 

34  9 

22.2 

23.2 

34.2 

21.6 

83.1 

106 

Lime,  nitrogen, 
phosphorus . . . 

57.3 

69.1 

88.4 

45.2 

68.5 

72.3 

45.6 

33.3 

55.6 

35.3 

42.2 

107 

Eime,  nitrogen, 
potassium 

53.3 

51.4 

75.9 

37.7 

39.7 

51.1 

42  2 

25.8 

46.2 

20.1 

55.6 

108 

Lime,  phosphorus, 
potassium.  . . 

58.7 

60.9 

80.0 

39.8 

41.5 

39.8 

27.2 

28.5 

43.0 

31.8 

79.7 

109 

Lime,  nitrogen, 
phos.,  potas. . 

58.7 

65.9 

82.5 

48.0 

69.5 

80.1 

52.8 

35.0 

58.0 

35.7 

57.2 

110 

Nitro.,  phos., 
potassium  ... 

60.0 

60.1 

85.0 

48.5 

63.3 

72.3 

44.1 

30.8 

64.4 

31.5 

54.1 

Average  Increase:  Bushels  per  Acre 


For  nitrogen 

-1.7 

3.4 

.7 

6.4 

14.1 

23.6 

19.3 

.1 

6.4 

1.6 

-40.1 

For  phosphorus  

1.7 

12.1 

10.7 

9.2 

16.5 

15.7 

6 4 

8.1 

16.3 

12.0 

5.4 

For  potassium  .... 

For  nitro.,  phos.,  over 

-3.0 

-2.9 

—5.1 

2.4 

—1.5 

1.0 

3.0 

— -2 

2.7 

- .6 

7.5 

phos 

For  phos.,  nitro.  over 
nitro 

-4.0 

6.8 

-4.1 

8.9 

23.7 

28.8 

20.0 

1.1 

3.6 

3.7 

-50.1 

— 2.7 

14.8 

10.9 

12.4 

26.8 

24.2 

9.3 

14.3 

26.6 

12.9 

16.9 

For  potas.,  nitro.,  phos. 

over  nitro. , phos. . . . 

1.4 

-3.2 

—5.9 

2.8 

1.0 

7,8 

7.2 

1.7 

2.4 

.4 

15.0 

Value  of  Crops  per  Acre  in  Eleven  Years 


Plot 

Soil  treatment  applied 

Total  value  of 
eleven  crops 

Value  of 
increase 

101 

102 

None  

T^jrnp  

$ 172.73 
184.75 

$ 12.02 

103 

Lime,  nitrogen  

167 . 42 

— 5.31 

104 

105 

Lime,  phosphorus 

Lime,  potassium.  ...  • ■ 

214.50 

173.22 

41.77 

.49 

106 

107 

Lime,  nitrogen,  phosphorus 

Lime,  nitrogen,  potassium 

233.15 

188.19 

60.42 

15.46 

108 

Lime,  phosphorus,  potassium 

200.37 

27.64 

109 

110 

Lime,  nitrogen,  phosphorus,  potassium 

Nitrogen,  phosphorus,  potassium 

244.62 

233.51 

71.89 

60.81 

Average  Value  of  Increase  per  Acre  in  Eleven  Years 

Cost  of 
increase 

For  nitrogen . . 

$ 15.14 
44.76 

$ 165.00 
27.50 

F or  phosphorus 

For  potassium 

For  nitrogen  and  phosphorus  over  phosphorus 

1.65 

18.65 

27.50 

165.00 

For  phosphorus  and  nitrogen  over  nitrogen 

65.73 

27.50 

For  potassium,  nitrogen,  and  phosphorus  over  nitrogen 

and  nhnsnhnriK  

11.47 

27.50 

14 


Son-  Report  No.  5 


[July, 


been  9 bushels  from  nitrogen  and  only  5 bushels  from  phosphorus,  while 
both  together  produced  an  increase  oi  33  bushels.  By  comparing  the  corn 
yields  for  the  four  years  1902,  1903,  ,906,  and  1907,  it  will  be  seen  that 
the  untreated  land  has  apparently  grow:  less  productive,  whereas  on  land 
receiving  both  phosphorus  and  nitrogen  ti  e yield  has  appreciably  increased, 
so  that  in  1907,  when  the  untreated  rotate  1 land  produced  only  34  bushels 
of  corn  per  acre,  a yield  of  72  bushels  (mom  than  twice  as  much)  was  pro- 
duced where  lime,  nitrogen,  and  phosphorus  had  been  applied,  altho  the  two 
plots  produced  exactly  the  same  yield  (57.3  bushels)  in  1902. 

Even  in  the  unfavorable  season  of  1910,  the  yield  of  the  highest-producing 
plot  exceeded  that  of  1902,  while  the  untreated  land  produced  less  than  half 
as  much  as  was  produced  in  1902.  The  prolonged  drouth  of  1911  resulted 
in  almost  a failure  of  the  corn  crop,  but  nevertheless  the  effect  of  soil  treat- 
ment is  seen.  Phosphorus  appears  to  have  been  the  first  limiting  element 
again  in  1909,  1910,  and  1911;  while  the  lodging  of  oats,  especially  on  the 
nitrogen  plots,  in  the  exceptionally  favorable  season  of  1912,  produced  very 
irregular  results. 

In  the  lower  part  of  Table  4 are  shown  the  total  values  per  acre  of  the 
eleven  crops  from  each  of  the  ten  different  plots,  the  amounts  varying  from 
$167.42  to  $244.62;  also  the  value  of  the  increase  produced  in  crop  yields 
above  the  value  of  the  yields  from  the  untreated  land,  corn  being  valued  at 
35  cents  a bushel,  oats  at  30  cents,  and  wheat  at  70  cents.  Phosphorus  with- 
out nitrogen  produced  $29.75  addition  to  the  increase  by  lime;  but,  with 
nitrogen,  it  produced  $65.73  above  the  crop  values  where  only  lime 
and  nitrogen  were  used.  The  results  show  that  in  25  cases  out  of  44  the 
addition  of  potassium  decreased  the  crop  yields.  Even  under  the  most  fa- 
vorable conditions,  and  with  no  effort  to  liberate  potassium  from  the  soil  by 
adding  organic  matter,  potassium  paid  back  less  than  half  its  cost. 

By  comparing  Plots  101  and  102,  and  also  109  and  no,  it  will  be  seen 
that  the  average  increase  produced  by  lime  was  $11.55,  or  more  than  $1  an 
acre  a year.  Altho  this  increase  may  have  been  above  normal  on  these  plots 
because  of  the  “condition”  of  the  soil  at  the  beginning,  it  suggests  that  the 
time  is  here  when  limestone  must  be  applied  to  some  of  these  brown  silt  loam 
soils.  While  nitrogen  produced  an  appreciable  increase,  especially  when 
phosphorus  was  provided,  the  only  conclusion  to  be  drawn,  if  we  are  to 
utilize  this  fact  to  advantage,  is  that  the  nitrogen  must  be  secured  from  the  air. 

Results  of  Experiments  on  Bloomington  Field 

Space  is  taken  to  insert  Table  5,  giving  all  of  the  results  thus  far  obtained 
from  the  Bloomington  soil  experiment  field,  which  is  also  located  on  the 
brown  silt  loam  prairie  soil  of  the  Illinois  corn  belt. 

The  general  results  of  the  eleven  years’  work  on  the  Bloomington  field 
tell  much  the  same  story  as  those  from  the  Sibley  field.  The  rotations  dif- 
fered by  the  use  of  clover  and  by  discontinuing  the  use  of  commercial  nitro- 
gen on  the  Bloomington  field  after  1905,  in  consequence  of  which  phosphorus 
without  commercial  nitrogen  (Plot  104)  produced  an  even  larger  increase 
($89.92)  than  was  produced  by  phosphorus  over  nitrogen  ($65.73)  on  the 
Sibley  field  (see  Plots  103  and  106). 

It  should  be  stated  that  a draw  runs  near  Plot  no  on  the  Bloomington 
field,  that  the  crops  on  that  plot  are  sometimes  djamaged  by  overflow  or  im- 
perfect drainage,  and  that  Plot  101  occupies  the  lowest  ground  on  the  oppo- 


La  Salle  County 


15 


1913] 

site  side  of  the  field.  In  part  because  of  these  irregularities  and  in  part  be- 
cause only  one  small  application  has  been  made,  no  conclusions  can  be  drawn 
in  regard  to  lime.  Otherwise  all  results  reported  in  Table  5 are  considered 
reliable.  They  not  only  furnish  much  information  in  themselves  but  also 
instructive  comparisons  with  the  Sibley  field. 

Wherever  nitrogen  was  provided,  either  by  direct  application  or  by  the 
use  of  legume  crops,  the  addition  of  the  element  phosphorus  produced  very 
marked  increases,  the  average  value  for  the  two  fields  being  $7.07  an  acre 
a year.  This  is  $4.57  above  its  cost  in  200  pounds  of  steamed  bone  meal, 
the  form  in  which  it  was  applied  to  the  Sibley  and  Bloomington  fields.  On 
the  other  hand,  the  use  of  phosphorus  without  nitrogen  will  not  maintain 
the  fertility  of  the  soil  (see  Plots.  104  and  106,  Sibley  field).  As  the  only 
practical  and  profitable  method  of  supplying  the  nitrogen,  a liberal  use  of 
clover  or  other  legumes  is  suggested,-  the  legume  to  be  plowed  under  either 
directly  or  as  manure,  preferably  in  connection  with  the  phosphorus  applied, 
especially  if  raw  rock  phosphate  is  used. 

From  the  soil  of  the  best  treated  plots,  160  pounds  per  acre  of  phos- 
phorus, as  an  average,,  were  removed  in  the  eleven  crops.  This  is  equal  to 
more  than  13  percent  of  the  total  phosphorus  contained  in  the  surface  soil  of 
an  acre  of  the  untreated  land.  In  other  words,  if  such  crops  could  be  grown 
for  eighty  years,  they  would  require  as  much  phosphorus  as  the  total  supply 
in  the  ordinary  plowed  soil.  The  results  plainly  show,  however,  that  without 
the  addition  of  phosphorus  such  crops  cannot  be  grown  year  after  year. 
Where  no  phosphorus  was  applied,  the  crops  removed  only  107  pounds  of 
phosphorus  in  the  eleven  years,  which  is  equivalent  to  only  9 percent  of  the 
total  amount  ( 1,200  pounds)  in  the  surface  soil  at  the  beginning  (1902).  The 
total  phosphorus  applied  from  1902'  to  1912,  as  an  average  of  all  plots  where 
it  was  used,  amounted  to  275  pounds  per  acre  and  cost  $27.50.  This  paid 
back  $84.91,  or  300  percent  on  the  investment;  whereas  potassium,  used  in 
the  same  number  of  tests  and  at  the  same  cost,  paid  back  only  $1.59  per  acre 
in  the  eleven  years,  or  less  than  6 percent  of  its  cost.  Are  not  these  results 
to  be  expected  from  the  composition  of  the  soil  and  the  requirements  of 
crops?  (See  Table  2,  page  7,  and  also  Table  A in  the  Appendix.) 

Nitrogen  was  applied  to  this  field  in  commercial  form  only,  from  1902 
to  1905 ; but  clover  was  grown  in  1906  and  1910,  and  a catch  crop  of  cow- 
peas  after  the  clover  in  1906.  The  cowpeas  were  plowed  under  on  all 
plots,  and  the  1910  clover  (except  the  seed)  was  plowed  under  on  five  plots 
(103,  106,  107,  109,  and  no).  Straw  and  corn  stalks  have  also  been  re- 
turned to  these  plots  in  recent  years.  The  effect  of  returning  these  residues 
to  the  soil  is  already  appreciable  (an  average  increase  of  4.4  bushels  of  wheat 
in  1910  and  7.9  bushels  of  corn  in  1911)  and  probably  will  be  more  marked 
on  subsequent  crops.  Indeed,  the  large  crops  of  corn,  oats,  and  wheat 
grown  on  Plots  104  and  108  during  the  eleven  years  drew  their  nitrogen 
very  largely  from  the  natural  supply  in  the  organic  matter  of  the  soil. 

The  clover  roots  and  stubble  contain  no  more  nitrogen  than  the  clover 
crop  takes  from  the  soil,  but  they  decay  rapidly  in  contact  with  the  soil  and 
probably  hasten  the  decomposition  of  the  soil  humus  and  the  consequent 
liberation  of  the  soil  nitrogen.  But  of  course  there  is  a limit  to  the  reserve 
stock  of  humus  and1  nitrogen  remaining  in  the  soil,  and  the  future  years  will 
undoubtedly  witness  a gradually  increasing  difference  between  Plots  104 
and  106  and  between  Plots  108  and  109,  in  the  yields  of  grain  crops. 


16 


Soil  Report  No.  5 


[July, 


Table  5.— Crop  Yields  in  Soil  Experiments,  Bloomington  Field 


Brown  silt  loam  prairie; 
early  Wisconsin 
glaciation 

Corn 

1902 

Corn 

1903 

Oats 

1904 

Wheat 

1905 

(clover 
! 1906 

Corn 

1907 

Corn 

1908 

Oats 

1909 

Clover2 

1910 

Wheat 

1911 

Corn 

1912 

O 

E 

Soil  treatment 
applied 

Bushels  or  tons  per  acre 

101 

None  

30.8 

63.9 

54.8 

30  8 

.39 

60.8 

40.3 

46.4 

1.56 

22.5 

55.2 

102 

Lime 

37.0 

60.3 

60.8 

28.8 

.58 

63.1 

35.3 

53.6 

1.09 

22.6 

47.9 

103 

Lime,  crop  res.1  .... 

35.1 

59.5 

69.8 

30.5 

.46 

64.3 

36.9 

49.4 

(.83) 

25.6 

62.5 

104 

Lime,  phosphorus. . 
Lime,  potassium  . . . 

41.7 

73.0 

72.7 

39.2 

1.65 

82.1 

47.5 

63.8 

4.21 

57.6 

74.5 

105 

37.7 

56.4 

S2.5 

33.2 

| .51 

64.1 

36.2 

45.3 

1.26 

21.7 

57.8 

106 

Lime,  residues,1 
phosphorus 

43  9 

77.6 

85.3 

50.9 

3 

78.9 

45.8 

72.5 

(1.67) 

60.2 

86.1 

107 

Lime,  residues,2 
potassium 

40.4 

58.9 

66.4 

29.5 

.81 

64.3 

31.0 

51.1 

(.33) 

27.3 

58.9 

108 

Lime,  phosphorus, 
potassium  

50.1 

74.8 

70  3 

37.8 

2.36 

81.4 

57.2 

59.5 

3.27 

54.0 

79.2 

109 

Lime,  res.,1  phos., 

52.7 

80.9 

90.5 

51.9 

8 

88.4 

58.1 

64.2 

(.42) 

60.4 

83.4 

110 

potassium 

Res  , phosphorus, 

52.3 

73.1 

71.4 

51.1 

3 

78.0 

51.4 

55.3 

(.60) 

61.0 

78.3 

potassium  j 

Average  Increase:  Bushels  or  Tons  per  Acre 


For  residues 

1.4 

3.1 

11.4 

5.9 

-.96 

1.3 

-1.1 

3.7 

-1.64 

4.4 

7.9 

For  phosphorus 

9.5 

17.8 

14.8 

14.4 

.41 

18.8 

18.0 

15.1 

1.51 

33.9 

24.0 

For  potassium 

5.8 

.2 

.3 

.7 

.25 

2.4 

4.2 

-4.8 

-.63 

-.6 

2.1 

For  res., phos. overphos. 

2 2 

4.6 

12.6 

11.7 

— .65 

-3.2 

-1.7 

8.7 

-2.25 

2.6 

11.6 

For  phos., res.  over  res. 
For  potas.,  res.,  phos. 

8^8 

18.1 

15.5 

20.4 

-1.46 

14.6 

8.9 

23.1 

.84 

34.6 

23.6 

over  res.,  phos 

8.8 

3.3 

5.2 

1.0 

.00 

9.5 

12.3 

-8.3 

-1.25 

.2 

—2.7 

Value  of  Crops  per  Acre  in  Eleven  Years 


Plotl 

Soil  treatment  applied 

Total  value  of 
eleven  crops 

Value  of 
increase 

101 

102 

$167.22 

165.52 

-$1.70 

L* 

ivim 

103 

1U4 

105 

L/ime  rpsidnps  ■ ...  .tTtt  

173.17 
255.44 
169 . 66 

5.95 

88.22 

2.44 

Lime,  phosphorus 

Lime  potassium 

106 

107 

108 

Iyime  residues,  phosphorus 

251.43 
170.57 
256  92 

84.21 

3.35 

89.70 

Lime,  residues,  potassium 

Lime,  phosphorus,  potassium  

109 

110 

Lime,  residues,  phosphorus,  potassium 

Residues,  phosphorus,  potassium  

254.76 

236.66 

87.54 

69.44 

Average  Value  of  Increase  per  Acre  in  Eleven  Years 

Cost  of 
increase 

For  residues 

For  phosphorus 

For  potassium  ...  

For  residues  and  phosphorus  over  phosphorus 

For  phosphorus  and  residues  over  residues 

For  potassium, residues,  and  phosphorus  over  residues 

and  phosphorus 

$ .60 
84.91 
1.59 
-4  01 
78.26 

3.33 

? 

$27.50 

27.50 

? 

27.50 

27.50 

'Commercial  nitrogen  was  used  1902-1905. 

2The  figures  in  parentheses  mean  bushels  of  seed;  the  others,  tons  of  hay. 
3Clover  smothered  by  previous  wheat  crop. 


La  Salle  County 


17 


1913] 


In  Plate  5 are  shown  graphically  the  relative  values  of  the  eleven  crops 
for  the  eight  comparable  plots,  Nos,  102  to  109.  The  cost  of  the  phosphorus 
is  indicated  by  that  part  of  the  diagram  above  the  short  crossbars.  It  should 
be  kept  in  mind  that  no  value  is  assigned  to  clover  plowed  under  except  as 
it  reappears  in  the  increase  of  subsequent  crops.  Plots  106  and  109  are 
heavily  handicapped  because  of  the  clover  failure  on  those  plots  in  1906  and 
the  poor  yield  of  clover  seed  in  1910,  whereas  Plots  104  and  108  produced 
a fair  crop  in  1906  and  a very  large  crop  in  1910.  As  an  average,  Plots  106 
and  109  are  only  $3.09  behind  Plots  104  and  108  in  the  value  of  the  eleven 
crops  harvested,  and  this  would  have  been  covered  by  about  bushel  more 
clover  seed  in  1906  or  1910,  or  it  may  be  covered  by  10  bushels  more  corn 
in  1913.  The  values  from  Plots  103  and  107  average  $4.28  more  than  the 
values  from  Plots  102  and  105.  (See  also  last  page  of  cover.) 


The  Subsurface  and  Subsoil 

In  Tables  6 and  7 are  recorded  the  amounts  of  plant  food  in  the  sub- 
surface and  the  subsoil,  but  it  should  be  remembered  that  these  supplies  are 
of  little  value  unless  the  top  soil  is  kept  rich.  Probably  the  most  important 
information  contained  in  Tables  6 and  7 is  that  the  most  common  upland 
timber  soil  is  usually  more  strongly  acid  in  the  subsurface  and  subsoil  than 
in  the  surface,  thus  emphasizing  the  importance  of  having  plenty  of  lime- 


102 

103 

104 

105 

106 

107 

108 

109 

0 

R 

P 

K 

RP 

RK 

PK 

RPK 

$165.52 

$173.17 

$255.44 

$169.66 

$251.43 

$170.57 

$256.92 

$254.76 

Plate  S.  Crop  Values  for  Eleven  Years, 
Bloomington  Experiment  Field 


18 


Soil  Report  No.  5 


[July, 


stone  in  the  surface  soil  to  neutralize  the  acid  moisture  which  rises  from  the 
lower  strata  by  capillary  action  during  periods  of  partial  drouth,  which  are 
critical  periods  in  the  life  of  such  plants  as  clover.  While  the  common 
brown  silt  loam  prairie  soil  is  usually  slightly  acid,  the  upland  soils  that  are 


Table  6.— Fertility  in  the  Soils  ok  La  Salle  County,  Illinois 
Average  pounds  per  acre  in  4 million  pounds  of  subsurface  (about  6J3  to  20  inches) 


Soil 

Total 

Total 

Total 

Total 

Total 

Total 

Lime- 

Lime- 

type 

Soil  type 

organic 

nitro- 

phos- 

potas- 

magne- 

cal- 

stone 

stone 

No. 

carbon 

gen 

phorus 

sium 

sium 

cium 

present 

requir’d 

Upland  Prairie  Soils 

1126 

Brown  silt  loam 

69139 

6163 

2184 

69646 

22877 

22973 

rarely 

often 

1126.3 

Brown  silt  loam 

on  till 

38520 

4160 

1480 

88560 

33520 

14040 

80 

1120 

Black  clay  loam 

82360 

7560 

28*0 

72320 

26160 

37960 

2040 

1125 

Black  silt  loam  . 

52720 

5280 

2920 

74040 

27360 

36260 

16620 

1160 

Brown  sandy 

loam 

34360 

3080 

1720 

60440 

16000 

16000 

1480 

Upland  Timber  Soils 

1134 

Yellow-gray  silt 

loam 

23947 

2280 

1907 

81853 

| 20840 

15187 

1427 

1135 

Y ellow  silt  loam 

17947 

2280 

1387 

90000 

27813 

10580 

8000 

Terrace  Soils 

1526 

Brown  silt  loam 

76907 

7507 

3067 

119680 

44133 

30573 

55987 

1526.4 

Brown  silt  loam 

on  gravel.  . 

56200 

5240 

1960 

67480 

21960 

18120 

120 

1526.5 

Brown  silt  loam 

on  rock 

198920 

16480 

10560 

94920 

30360 

49800 

15160 

1527 

Brown  silt  loam 

over  gravel. . - 

45760 

4600 

1760 

71080 

19200 

12920 

120 

1534.4 

Yellow-gray  silt 

loam  on  gravel 

19720 

2480 

2000 

70840 

20160 

17120 

80 

1536 

Yellow-gray  silt 

loam  over 

gravel 

15880 

2120 

1840 

79640 

20280 

16160 

440 

1560 

Brown  sandy 

loam 

31680 

2900 

2040 

38380 

6860 

9740 

80 

1560.4 

Brown  sandy 

loam  on  gravel 

28400 

2760 

2440 

56240 

11880 

9480 

80 

1560 . 5 

Brown  sandy 

loam  on  rock . 

67720 

5880 

2480 

25160 

9920 

15440 

3920 

1564 

Yellow- gray 

sandy  loam 

over  gravel. . . 

12440 

1600 

1680 

64480 

12760 

13280 

80 

1581 

Dune  sand 

12750 

1200 

1350 

44200 

8400 

10800 

150 

1590 

Gravelly  loam . . 

103760 

10000 

3680 

51800 

41280 

80360 

153720 

Swamp  and  Bottom-Land  Soils 

1426 

Deep  brown  silt 

loam 

98560 

9160 

4120 

83480 

63400 

128560 

428120 

1454 

Mixed  loam 

(small  streams) 

36560 

4560 

2040 

56520 

81600 

127880 

542960 

1401 

Deep  peat  .... 

546860 

46740 

2360 

14640 

15680 

157680 

265880 

1402 

Medium  peat  on 

clay  • 

195720 

19140 

1620 

28640 

12780 

26400 

2580 

Residual  Soils 

060.5 

Brown  sandy 

13440 

1480  I 

1600 

57800 

11320 

1720 

1040 

loam  on  rock. 

083 

Residual  sand . . 

12000 

1200 

1250 

10450 

3600 

1800 

500 

La  Salle  County 


19 


W3] 

or  were  timbered  are  already  distinctly  in  need  of  limestone,  as  a rule ; and, 
as  already  explained,  they  are  even  more  deficient  in  phosphorus  and  nitrogen 
than  the  common  prairie  soil. 


Table  7.— Fertility  in  the  Soils  of  La  Salle  County,  Illinois 
Average  pounds  per  acre  in  6 million  pounds  of  subsoil  (about  20  to  40  inches) 


Soil 

Total 

Total 

Total 

Total 

Total 

Total 

Lime- 

Lime 

type 

Soil  type 

organic 

nitro- 

phos- 

potas- 

magne- 

cal- 

stone 

| stone 

No. 

carbon 

gen 

phorus 

sium 

sium 

cium 

present 

requir'd 

Upland  Prairie  Soils 


1126 

Brown  silt  loam 

21886 

2683 

3048 

109387 

57857 

61769 

often 

rarely 

1126.3 

Brown  silt  loam 

on  till 

21300 

3660 

2400 

178200 

205620 

250320 

1167840 

1120 

Black  clay  loam 

45240 

4500 

3360 

109320 

40320 

43200 

2580 

1125 

Black  silt  loam . 

14610 

2370 

3840 

112020 

66090 

87480 

205830 

1160 

Brown  sandy 

loam 

21120 

2700 

2520 

100380 

38220 

32820 

240 

Upland  Timber  Soils 


1134 

Y ellow-gray  silt 

loam 

23500 

2460 

3280 

133040 

68360 

76760 

3510 

1135 

j Yellow  silt  loam 

22840 

3100 

2540 

170560 

101860 

62240 

371520 

Terrace  Soils 


1526 

Brown  silt  loam 

50340 

5840 

3440 

178820 

90440 

92420 

347900 

1526.4 

Brown  silt  loam 

on  gravel 

49560 

5100 

3360 

93300 

48060 

31440 

300 

1527 

Brown  silt  loam 

over  gravel. . . 

30540 

3420 

2940 

107700 

34920 

21720 

600 

1534.4 

Y ellow-gray  silt 

loam  on  gravel 

1536 

Yellow-gray  silt 

loam  over 
gravel  . . . 

19260 

3180 

3600 

117360 

38520 

28020 

1440 

1560 

Brown  sandy 

loam 

19350 

1470 

1830 

59640 

10830 

12420 

90 

1564 

Y ello w - gray 

sandy  loam 
over  gravel. . . 

11760 

1620 

2760 

83460 

22320 

17940 

420 

1581 

Dune  sand 

19130 

1800 

2030 

66300 

12600 

16200 

230 

Swamp  and  Bottom-Land  Soils 


1426 

Deep  brown  silt 

loam.. 

136200 

13740 

5820 

125340 

126000 

205140 

728040 

1454 

Mixed  loam 

(small  streams) 

20880 

2100 

2160 

68400 

137220 

261360 

1045980 

1401 

Deep  peat  

820290 

70110 

3540 

21960 

23520 

236520 

398820 

1402 

Medium  peat  on 

clay 

49500 

4140 

3660 

102660 

135240 

395280 

1124100 

Residual  Soils 

083  | Residual  sand. . 

18000  | 1800  | 1880  15680 1 

5400 

2700 

750 

20 


Soil  Report  No.  5 


[July, 


INDIVIDUAL  SOIL  TYPES 
(a)  Upland  Prairie 

Brown  Silt  Loam  (1126;  also  926  on  Moraines ) 

This  type  occupies  922.16  square  miles,  or  590,182  acres,  and  constitutes 
79.7  percent  of  the  entire  area  of  the  county.  In  topography  it  varies  from 
flat  to  rolling,  the  average  being  what  would  be  called  gently  rolling  with 
irregular  undulations  due  to  the  action  of  the  glacier  in  thus  depositing  mate- 
rial. In  many  places  the  surface  is  not  sufficiently  rolling  for  good  drainage, 
and  it  has  been  necessary  to  use  tile  drainage  to  a large  extent. 

The  soil  to  a depth  of  3 to  5 feet  is  formed  from  wind-blown  loessial 
material  similar  in  origin  to  the  deep  loess  deposits  found  near  the  great 
stream  valleys,  but  finer  in  physical  composition.  This  type,  altho  typically 
a prairie  soil,  may  include  in  its  area  a small  amount  of  land  that  has  been 
forested  in  comparatively  recent  time. 

The  surface  soil,  o to  6^3  inches,  is  a brown  silt  loam,  varying  on  the 
one  hand  to  black  as  it  grades  into  black  clay  loam  (1120)  or  black  silt  loam 
(1125),  and  on  the  other,  to  grayish  brown  or.  yellowish  brown  as  it  grades 
into  the  timber  types.  It  contains  a sufficient  amount  of  the  coarser  con- 
stituents (coarse  silt  and  sand)  to  make  it  work  easily  and  yet  enough  of 
fine  silt  and  clay  to  give  it  stability.  The  organic-matter  content  varies  from 
4.2  to  8.7  percent,  with  an  average  of  5.9  percent;  in  other  words,  from 
42  to  87  tons  per  acre,  with  an  average  of  59  tons.  It  is  less  in  the  more 
rolling  areas,  while  in  the  low  and  poorly  drained  parts  it  is  greater,  the 
larger  moisture  content  having  permitted  a ranker  growth  of  grasses  and 
roots  with  more  favorable  conditions  for  their  preservation. 

The  subsurface  stratum  varies  in  thickness  from  9 to  16  inches  and  in 
color  from  a dark  brown  to  a yellowish  brown  silt  loam.  Both  color  and 
depth  vary  with  the  topography,  being  lighter  and  shallower  on  the  more 
rolling  areas  and  the  areas  where  this  type  grades  into  the  timber  types. 

The  beginning  of  the  subsoil  is  indicated  by  a change  in  color  and  texture. 
It  is  a yellow  clayey  silt  or  silty  clay,  somewhat  plastic  when  wet.  Where 
the  drainage  has  been  good,  it  is  of  a bright  or  a pale  yellow  color,  but  where 
poorly  drained,  it  approaches  an  olive. 

A phase  of  this  type  has  been  recognized  in  this  county  where,  by  the 
removal  of  part  of  the  fine  loessial  material,  the  glacial  drift  or  till  is  found 
less  than  30  inches  from  the  surface.  In  some  places  this  may  give  a some- 
what inferior  soil  owing  to  the  compact  and  less  pervious  character  of  the 
subsoil.  But  this  does  not  occur  very  often;  most  of  the  till  in  this  type  is 
pervious,  and  some  of  it  in  Townships  33  and  34,  Range  5 East,  is  quite 
gravelly.  Limited  areas  of  sandy  and  gravelly  loam,  too  small  to  be  shown 
on  the  map,  are  quite  common  in  the  morainal  regions. 

In  the  management  of  this  type,  one  very  important  thing,  aside  from 
proper  fertilization,  tillage,  and  drainage,  is  to  keep  it  in  good  physical  con- 
dition, or  good  tilth.  It  is  a common  practice  in  the  corn  belt  to  pasture 
the  corn  stalks  during  the  winter  and,  too  often,  rather  late  in  the  spring 
after  the  ground  has  thawed  out.  This  tramping  puts  the  soil  in  bad  condi- 
tion for  working.  It  becomes  partially-  puddled  and  will  be  cloddy  as  a re- 
sult. If  tramped  too  late  in  the  spring,  the  natural  agencies  of  freezing  and 
thawing  and  wetting  and  drying,  with  the  aid  of  ordinary  tillage,  fail  to  pro- 


La  Salle  County 


21 


1913] 

duce  good  tilth  before  the  crop  is  planted.  Whether  the  crop  is  corn  or  oats, 
it  necessarily  suffers,  and  if  the  season  is  dry,  much  damage  may  result.  If 
the  field  is  put  in  corn,  a poor  stand  is  likely  to  follow  and  if  put  in  oats,  a 
compact  soil  is  formed  which  is  unfavorable  for  their  growth.  Sometimes 
farmers  work  their  soil  when  too  wet.  This  also  produces  a partial  puddling 
which  is  unfavorable  to  physical,  chemical,  and  biological  processes.  The 
bad  effect  will  be  greater  if  cropping  has  reduced  the  amount  of  organic  mat- 
ter below  the  amount  that  is  necessary  to  maintain  good  tilth. 

Every  practicable  means  should  be  used  to  maintain  the  supply  of  organic 
matter.  Clover  should  be  grown  every  three  or  four  years  and  the  bulk  of 
the  crop  turned  under  either  directly  or  as  manure.  All  straw  should  be  re- 
turned to  the  land  and  plowed  under  if  not  used  for  bedding  or  feed.  One 
of  the  chief  sources  of  loss  of  organic  matter  in  the  corn  belt  is  the  practice 
of  burning  the  corn  stalks.  Could  the  farmers  be  made  to  realize  how  great 
a loss  this  entails,  they  would  certainly  discontinue  the  practice.  Probably 
no  form  of  organic  matter  acts  more  beneficially  in  producing  good  tilth 
than  corn  stalks,  and  to  burn  them  is  a very  serious  waste. 

The  stalks  should  be  cut  up  with  a disk  or  stalk  cutter  and  turned  under. 
It  is  true  that  they  decay  rather  slowly,  but  it  is  also  true  that  their  durability 
in  the  soil  after  partial  decomposition  is  exactly  what  is  needed  in  the  main- 
tenance of  an  adequate  supply  of  humus.  A ton  of  dry  corn  stalks  incor- 
porated with  the  soil  will  ultimately  furnish  as  much  humus  as  four  tons  of 
average  farm  manure,  but,  when  burned,  both  the  humus-making  material 
and  the  nitrogen  are  forever  destroyed  and  lost. 

The  normal  and  the  lighter  phases  of  brown  silt  loam  already  require 
liberal  additions  of  nitrogenous  organic  matter  and  phosphorus  for  the  in- 
crease and  maintenance  of  their  crop-producing  power.  As  a rule,  limestone 
can  also  be  added  with  profit,  and  the  importance  of  using  limestone  becomes 
greater  year  after  year.  The  heavier  phase  of  this  soil  type,  usually  found  in 
narrow  areas  along  old  sloughs  or  draws,  is  still  rich  in  humus  and  nitrogen, 
moderately  rich  in  phosphorus,  and  well  supplied  with  lime  carbonate.  Often 
the  soil  type  in  these  narrow  strips  is  black  silt  loam  (1125),  but  it  is  in 
too  small  areas  to  map  separately  from  the  brown  silt  loam.  It  should  be 
kept  in  mind  that  phosphorus  is  a constituent  of  humus  and  is  usually  asso- 
ciated with  limestone;  and  phosphorus  is  not  likely  to  be  greatly  needed 
where  the  soil  is  still  rich  in  humus  and  shows  the  presence  of  limestone  by 
foaming  when  moistened  with  strong  hydrochloric  acid.  (See  Circular  150 
for  detailed  directions  for  testing  the  soil  for  limestone  or  acidity.) 

Black  Clay  Loam  (1120) 

This  type  comprises  6.4  square  miles,  or  4,096  acres,  and  constitutes  about 
Yi  percent  of  the  total  area  of  the  county.  It  occupies  the  lower  and  flatter 
areas  where  the  accumulation  of  organic  matter  and  finer  soil  constituents 
has  been  going  on.  It  has  poor  natural  drainage,  and  was  originally  in 
swamps  or  sloughs,  but  by  means  of  artificial  drainage,  it  has  been  com- 
pletely reclaimed.  Altho  the  soil  is  fine-grained,  it  drains  well,  having  a 
large  number  of  checks,  or  joints,  which  make  it  quite  permeable  to  water. 
The  openings  produced  by  worms  and  crayfish  and  deep-rooting  plants  have 
further  increased  this  permeability. 

The  surface  soil,  o to  67^  inches,  is  a black  clay  loam,  plastic  and  granu- 
lar, varying  locally  to  a black  clayey  silt  loam  where  much  silt  has  been 


Soil  Report  No.  5 


[July, 


washed  in  covering  the  more  clayey  layer.  It  is  very  well  supplied  with  or- 
ganic matter,  containing  about  7 percent.  A considerable  percentage  of 
sand,  chiefly  of  the  finer  grades,  may  be  found  in  this  stratum. 

The  subsurface  soil,  6;H  to  18  or  20  inches,  varies  from  a black  to  a 
brown  clay  loam,  usually  somewhat  heavier  than  the  surface  stratum. 

The  subsoil,  extending  to  a depth  of  40  inches,  is  a dark  drab,  mottled  or 
yellow  clay  loam,  varying  locally  to  a yellowish  clayey  silt.  It  frequently 
contains  concretions  of  lime. 

In  the  management  of  this  type,  the  most  important  thing  is  to  keep  it 
in  good  tilth.  To  do  this,  thoro  drainage  is  the  first  essential.  Then  it  is 
necessary  to  use  every  means  to  maintain  the  supply  of  organic  matter,  for, 
it  must  be  remembered,  heavy  clay  soils  become  difficult  to  work  in  proportion 
as  the  organic  matter  is  removed.  Continued  burning  of  corn  stalks  on  this 
type  of.  soil  will  finally  result  in  great  injury  to  its  tilth  and  working  condi- 
tion. 

Clover  is  especially  beneficial  to  this  black  clay  loam,  as  it  loosens  it  up 
to  a considerable  depth  and  gives  greater  permeability  to  moisture  and  roots. 
However,  it  is  not  immediately  necessary  that  so  much  clover  or  manure  be 
plowed  under  on  this  type  as  on  the  brown  silt  loam. 

As  yet  no  field  experiments  have  been  conducted  on  black  clay  loam,  but, 
where  the  soil  contains  sufficient  limestone  to  respond  to  the  test  with 
strong  acid,  there  is  no  need  to  add  more,  unless  for  physical  improvement. 
No  marked  profit  can  be  expected  from  adding  phosphate,  altho  it  will 
doubtless  pay  to  keep  the  phosphorus  content  up  to  at  least  its  present  per- 
centage. 

Black  Silt  Loam  (1125) 

This  type  occupies  low,  flat  areas  of  prairie  land  somewhat  similar  to 
those  of  the  black  clay  loam  (1120),  but  it  has  had  more  of  the  coarser  ma- 
terial washed  in,  and  as  a result  is  somewhat  friable.  It  covers  a total  area 
of  17.39  square  miles,  or  11,129  acres,  comprising  about  1.5  percent  of  the 
entire  area  of  the  county.  In  topography  this  type  is  flat  and  poorly  drained 
naturally. 

The  surface  soil,  o to  6^3  inches,  is  a black  silt  loam  varying  on  the  one 
hand  to  brown  silt  loam,  and  on  the  other  to  black  clay  loam.  It  is  very 
granular  and  pervious  to  wrater.  The  organic-matter  content  is  about  6.4 
•percent,  or  64  tons  per  acre. 

The  subsurface,  62/$  to  20  inches  or  more,  is  a black  to  dark  brown 
clayey  silt  loam  quite  pervious  to  water.  It  contains  2.27  percent  of  organic 
matter,  or  45  tons  per  acre. 

The  subsoil  is  a yellow  or  drabbish  yellow  slightly  clayey  silt  that  allows 
free  movement  of  water. 

In  the  management  of  this  black  silt  loam,  the  same  precautions  should 
be  observed  as  in  that  of  black  clay  loam  (1120).  The  black  silt  loam  con- 
tains less  clay  and  more  silt  and  limestone  than  the  black  clay  loam,  but 
otherwise  the  two  types  are  very  much  alike  in  composition  and  requirements. 

Brown  Sandy  Loam  (1160) 

A small  area  of  about  13  acres  of  rather  coarse  brown  sandy  loam  occurs 
in  Section  27,  Township  36  North,  Range  2 East,  that  does  not  differ  greatly 
in  fertility  from  the  brown  silt  loam  around  it.  This  is  the  only  area  of 
this  type  in  the  county. 


La  Salle  County 


23 


1913] 

Since  this  type  is  somewhat  sour  in  all  strata  to  a depth  of  40  inches, 
the  use  of  2 to  5 tons  per  acre  of  ground  limestone  should  prove  profit- 
able, especially  for  the  production  of  alfalfa  or  of  clover  in  crop  rotation. 
For  a sandy  loam,  it  is  well  supplied  with  phosphorus,  considering  the  deep- 
feeding  range  afforded  to  plant  roots  ; but  legume  crops  should  have  a promi- 
nent place  in  the  crop  rotation  and  the  nitrogen  should  be  maintained  by 
organic  manures. 

(b)  Upland  Timber  Soils 

The  upland  timber  soils  differ  from  the  prairie  soils  principally,  in  the 
fact  that  they  contain  less  organic  matter.  This  low  organic-matter  con- 
tent produces  another  striking  difference,  that  of  color,  the  prairie  soils  be- 
ing black  or  brown,  while  the  timber  soils  are  yellow  or  gray. 

Yellow-Gray  Silt  Loam  (1134,  or  934  when  found  on  morainal  ridges ) 

This  type  covers  94.56  square  miles  (60,518  acres)  or  8.17  percent  of  the 
entire  area  of  the  county.  It  is  located  almost  without  exception  on  the  up- 
land along  the  larger  streams,  and  comprises  the  less  rolling  areas  that  have 
been  forested.  The  natural  drainage  systems  have  been  better  developed  in 
this  type  than  in  any  other  except  the  yellow  silt  loam  (1135). 

The  surface  6%  inches  is  a gray,  yellowish  gray,  or  brownish  gray  silt 
loam,  the  color  varying  with  the  topography ; the  nearly  level  areas  usually  are 
either  lighter  or  darker  in  color,  while  the  more  rolling  parts  have  more  of 
a yellow  or  brownish  yellow  color.  The  organic-matter  content  also  varies 
with  the  topography  and  with  the  length  of  time  in  forest  as  indicated  by 
the  character  of  the  trees,  but  it  averages  2.8  percent,  or  28  tons  per  acre 
6^  inches  deep. 

The  subsurface  soil,  6^3  to  12  or  18  inches,  is  usually  a gray  to  grayish 
yellow  silt  loam.  The  thickness  of  this  stratum  varies  with  the  topography, 
being  thinner  on  the  more  rolling  areas.  The  amount  of  organic  matter 
present  is  about  21  tons  for  4 million  pounds  of  soil. 

The  subsoil,  extending  to  a depth  of  40  inches,  is  a somewhat  plastic 
yellow  or  grayish  yellow  clayey  silt,  the  lower  part  sometimes  reaching  the 
glacial  drift.  This  is  due  to  the  removal  by  erosion  of  a large  part  of  the 
loessial  material.  This  glacial  drift  may  be  locally  a very  gravelly  deposit, 
but  usually  it  is  a gravelly  clay  that  may  be  lacking  in  permeability.  Other- 
wise each  stratum  of  this  type  is  quite  pervious  to  water,  with  the  exception 
of  the  level  gray  areas,  where  a tight,  more  or  less  compact  clayey  layer  has 
formed.  This  occurs  only  in  areas  too  small  to  be  shown  on  the  map. 

This  type  is  low  in  organic  matter,  and  one  of  the  first  considerations  for 
physical  improvement  is  the  problem  of  how  to  increase  this  constituent.  It 
is  scarcely  possible  under  the  present  system  of  cropping  even  to  maintain 
the  supply  of  organic  matter,  much  less  to  increase  it.  Crop  residues  must 
be  turned  back  either  directly  or  in  manure,  the  corn  stalks  must  be  cut  up 
and  turned  under  instead  of  being  burned,  straw  should  be  returned,  clover 
grown  and  turned  under,  and  pasture  may  be  used  to  good  advantage.  Ero- 
sion should  be  prevented  as  much  as  possible,  not  only  on  this  type,  but  on 
all  others  as  well.  Soils  rich  in  organic  matter  are  much  less  likely  to  erode 
because  of  the  effect  of  the  organic  matter  on  permeability  and  granulation. 

Aside  from  its  low  content  of  organic  matter,  this  soil  has  a very  good 
physical  composition.  It  has  a good  topography,  and  affords  excellent  con- 
ditions for  drainage.  After  the  brown  silt  loam,  it  is  by  far  the  most  im- 


24  Soil  Report  No.  5 [July, 

portant  type  of  soil  in  the  county.  It  occupies  60,000  acres  of  land,  or  five 
times  as  much  as  any  less  extensive  all-tillable  type. 

On  the  whole,  the  yellow-gray  silt  loam  offers  one  of  the  best  opportuni- 
ties for  profitable  soil  improvement,  and  its  improvement  is  more  a matter  of 
procedure  than  of  experiment.  The  soil  is  normal  in  general  character,  and 
its  chemical  composition  plainly  reveals  what  is  required  for  improvement ; 
namely,  limestone,  nitrogenous  organic  matter,  and  phosphorus. 

This  type  is  acid  in  the  surface,  more  acid  in  the  subsurface,  and  still 
more  acid  in  the  subsoil.1  An  application  of  about  2 tons  of  limestone  and 
half  a ton  of  fine-ground  rock  phosphate  every  four  years,  with  plenty  of 
clover  and  crop  residues  or  farm  manure,  will  gradually  work  improvement ; 
and,  if  one  is  prepared  to  make  the  investment,  the  initial  applications  may 
well  be  5 tons  of  limestone  and  even  3 or  4 tons  of  phosphate.  With  38,580 
pounds  in  the  surface  soil  of  an  acre,  the  potassium,  problem  is  merely  one  of 
liberation,  and  with  even  slight  erosion,  which  is  certain  to  occur  where  the 
surface  drainage  is  good,  the  gradual  renewal  from  the  still  greater  abund- 
ance in  the  subsurface  and  subsoil  insures  a permanent  supply  of  potassium 
for  rational  systems  of  either  grain  farming  or  live-stock  farming.  In  com- 
parison, analysis  reveals  only  1,033  pounds  of  total  phosphorus  in  the  surface 
soil  of  an  acre  and  a still  lower  proportionate  amount  in  the  subsurface. 

For  definite  results  from  the  most  practical  field  experiments  upon  typical 
yellow-gray  silt  loam,  we  must  go  down  into  “Egypt,”  where  the  people  of 
Saline  county,  especially  those  in  the  vicinity  of  Raleigh  and  Galatia,  have 
provided  the  University  with  a very  suitable  tract  of  this  type  of  soil  for  a 
permanent  experiment  field.  Here,  as  an  average  of  triplicate  tests  each  year, 
the  yield  of  corn  on  untreated  land  was  25.3  bushels  in  1910,  23.6  bushels  in 

1911,  and  22  bushels  in  1912;  while  the  corresponding  averages  from  land 
treated  with  heavy  applications  of  limestone  and  a limited  amount  of  organic 
manures  were  41.4  bushels  in  1910,  41.3  bushels  in  1911,  and  50.1  bushels  in 

1912,  the  corn  being  grown  on  a different  series  of  plots  every  year  in  a four- 
year  rotation  of  wheat,  corn,  oats,  and  clover.  About  the  same  proportionate 
increases  were  produced  in  wheat  and  hay,  and  the  effect  on  oats  was  also 
marked. 

Owing  to  the  low  supply  of  organic  matter  and  limestone,  phosphorus 
produced  no  benefit,  as  an  average,  during  the  first  two  years,  but  with  in- 
creasing supplies  of  organic  matter  the  effect  of  phosphorus  is  seen  in  the 
1912  crops.  Of  course,  a single  four-year  rotation  cannot  be  practiced  in 
three  years,  and  the  full  benefit  of  the  system  of  rotation  and  soil  treatment 
is  not  to  be  expected  before  the  third  or  fourth  four-year  period. 

While  limestone  is  the  material  first  needed  for  the  economic  improve- 
ment of  the  more  acid  soil  of  southern  Illinois,  with  organic  manures  and 
phosphorus  to  follow  in  order,  the  less  acid  soils  of  the  central  and  northern 
parts  of  the  state  are  frequently  most  deficient,  relatively,  in  phosphorus  and 
organic  matter. 

Table  8 shows  in  detail  eleven  years’  results  secured  from  the  Antioch  soil 
experiment  field  located  in  Lake  county  on  the  yellow-gray  silt  loam  of  the 
late  Wisconsin  glaciation.  In  acidity,  this  type  in  La  Salle  county  is  inter- 
mediate between  the  similar  soils  in  Saline  and  Lake  counties,  but  no  ex- 
periment field  has  been  conducted  on  this  important  soil  type  in  the  early 
Wisconsin  glaciation. 

JIn  one  set  of  soil  samples,  limestone  was  found  in  the  lower  stratum,  but  this  is 
unusual  (as  when  till  is  found  within  40  inches)  and  it  was  not  included  in  the  average. 


La  Salle  County 


■rPL?] 


Table  8. — Crop  Yields  in  Soil  Experiments,  Antioch  Field 


Yellow-gray  silt  loam, 
undulating  timber- 
land;  late  Wisconsin 
glaciation 

Corn 

1902 

Corn 

1903 

Oats 

1904 

Wheat 

1905 

: Corn 
1906 

Corn 

1907 

Oats 

1908 

Wheat 

1909 

Corn 

1910 

Corn 

1911 

| Oats 
i 1912 

1 

applied 

Bushels  per  acre 

101 

None1 

44.8 

36.6 

17.8 

18.5 

35.9 

12.4 

65.6 

12.2 

5.2 

34.4 

21.3 

102 

Lime 

45.1 

38.9 

12.8 

10.3 

31.5 

9.5 

61.6 

11.7 

3.0 

24.6 

17.5 

103 

Lime,  nitrogen . . . 

46.3 

40.8 

2.8 

j 17.8 

37.8 

6.4 

60.3 

13.0 

1.4 

10.4 

24.4 

104 

Lime,  phosphorus 

50.1 

53.6 

12.5 

| 35.8 

57.4 

13.4 

70.9 

23.3 

6.8 

37.4 

49.1 

10S 

Lime,  potassium  . 

48.2 

50.2! 

9"  7 

21 . 7 

34.9 

12.9 

62.5 

13.5 

4.6 

20.4 

18.8 

106 

Lime,  nitro.,  phos. 

56.6 

62.7 

15.9 

15.2 

59.3 

20.9 

1 49.1 

33.8 

6.0 

37.0 

46.9 

107 

Eime,nitro.,potas. 

52.1 

54.9 

10  3 

11.8 

39.0 

11.1 

52.6 

21.0 

1.6 

7.0 

16.9 

108 

Lime, phos.,  potas. 

60.7 

66.0 

19.7 

28.7 

59.1 

18.3 

59.4 

26.2 

3.2, 

42.2 

35.9 

109 

Lime,  nitro., phos. 

potas 

61.2 

69.1 

31.9 

18.0 

65.9 

31.4 

51.9 

30.5 

3.0 

44.2 

31.9 

110 

Nitro., phos., potas. 

59.7 

71.8 

37.2 

16.3 

66.3 

28.8 

55.9 

34.5 

4 ■ 0| 

49.0 

38.1 

Average  Increase:  Bushels  per  Acre 


For  nitrogen  

3.0 

4.7 

1.6 

-8.4 

4.8 

3.9 

-10.1 

5.9 

-1.4 

-6.5 

-.3 

For  phosphorus  

9.2 

16.7 

11.1 

9.0 

24.6 

11.0 

-1.4 

13.7 

2.1 

24.6 

21.6 

For  potassium 

For  nitro.,  phos.  over 

6.0 

11.0 

6.9 

.3 

3.2 

5.9 

-3.9 

2.3 

-1.2 

1.1 

-8.6 

phos.  

For  phos.,  nitro.  over 

6.5 

9.1 

3.4 

-20.6 

. 1.9 

7.5 

-21.8 

10.5 

-.8 

-.4 

2.2 

nitro 

For  potas.,  nitro.,  phos. 

10.3 

21.9 

13.1 

-2.6 

21.5 

14.5 

-11.2 

20.8 

4.6 

26.6 

22.5 

over  nitro.,  phos 

4.6 

6.4 

16.0 

2.8 

6.6 

10.5 

2.8 

-3.3 

-3.0 

7.2 

-15.0 

Value  of  Crops  per  Acre  in  Eleven  Years 


Plot 

Soil  treatment  applied 

Total  value 
of  eleven 
crops 

Value  of 
increase 

101 

None 

$112  16 

102 

Lime 

96.38 

1 £ *7Q 

$ — JLo . /o 

103 

Eime,  nitrogen 

97.89 

—14.27 

104 

Lime,  phosphorus  . 

157.67 

45.51 

105 

Eime,  potassium 

111.86 

-.30 

106 

Eime,  nitrogen,  phosphorus 

152.75 

40.59 

107 

Eime,  nitrogen,  potassium 

104.89 

—7.27 

108 

Lime,  phosphorus,  potassium  

160.25 

48.09 

109 

Lime,  nitrogen,  phosphorus,  potassium 

164.83 

52.67 

110 

Nitrogen,  phosphorus,  potassium 

172.78 

60.62 

Average  Value  of  Increase  per  Acre  in  Eleven  Years 

Cost  of 

increase 

For  nitrogen 

$ 1 45 

no 

For  phosphorus 

56.12 

27.50 

For  potassium 

9.28 

For  nitrogen  and  phosphorus  over  phosphorus 

—4.92 

165.00 

For  phosphorus  and  nitrogen  over  nitrogen 

54.86 

27.50 

For  potassium,  nitrogen,  and  phosphorus  over  nitroeren  and 

phosphorus 

12.08 

27.50 

‘Plot  101,  the  check  plot,  is  the  lowest  ground  but  it  is  well  drained  and  is  appre- 
ciably better  land  than  the  rest  of  the  field.  Plot  102  is  a more  trustworthy  check  plot. 


26 


Soil  Report  No.  5 


Uuly, 


The  Antioch  field  was  started  in  order  to  learn  as  quickly  as  possible  just 
what  effect  would  be  produced  by  the  addition  of  nitrogen,  phosphorus,  and 
potassium,  singly  and  in  combination.  These  elements  have  all  been  added  in 
commercial  form.  Only  a small  amount  of  lime  was  applied  at  the  beginning, 
and  with  the  abnormality  of  Plot  1 and  with  an  abundance  of  limestone  in 
the  subsoil  (a  common  condition  in  the  late  Wisconsin  glaciation),  no  con- 
clusions can  be  drawn  regarding  the  effect  of  lime. 

As  an  average  of  44  tests  (4  each  year  for  11  years),  liberal  applications 
of  commercial  nitrogen  produced  a slight  decrease  in  crop  values,  phosphorus 
paid  back  200  percent  of  its  cost,  while  each  dollar  invested  in  potassium 
brought  back  only  34  cents  (a  net  loss  of  66  percent).  Thus,  while  the 
detailed  data  show  great  variation,  owing  both  to  some  irregularity  of  soil 
and  to  some  very  abnormal  seasons,  with  three  almost  complete  crop  failures 
(1904,  1907,  and  1910),  yet  the  general  summary  strongly  confirms  the 
analytical  data  in  showing  the  need  of  applying  phosphorus  and  the  profit 
from  its  use,  and  the  loss  in  adding  potassium.  In  most  cases  commercial 
nitrogen  damaged  the  small  grains  by  causing  the  crop  to  lodge;  but  when- 
ever a corn  yield  of  40  bushels  or  more  was  secured  where  phosphorus  was 
applied  either  alone  or  with  potassium,  then  the  addition  of  nitrogen  pro- 
duced an  increase.  From  a comparison  of  the  results  from  the  Sibley  and 
Bloomington  fields,  we  must  conclude  that  better  yields  are  to  be  secured  by 
providing  nitrogen  thru  the  growing  of  legume  crops  in  the  rotation  rather 
than  by  the  use  of  commercial  nitrogen,  which  is  evidently  too  readily  avail- 
able, causing  too  rapid  growth  and  consequently  weakness  of  straw ; and  of 
course  the  most  economic  source  of  nitrogen,  where  that  element  is  needed 
for  soil  improvement  in  general  farming,  is  the  atmosphere.  (See  Appendix 
for  detailed  discussion  of  “Permanent  Soil  Improvement.”) 

Yellow  Silt  Loam  (1135  or  935) 

This  type,  like  the  preceding,  is  found  principally  along  the  large  streams, 
but  it  also  includes  other  hilly  and  broken  land  unsuited  for  ordinary  agri- 
culture. It  comprises  41.12  square  miles,  or  26,317  acres,  and  constitutes 
3.55  percent  of  the  total  area  of  the  county.  The  development  of  natural 
drainage  channels  has  been  carried,  to  excess,  and  altho  perfectly  surface- 
drained  this  land  has  been  spoiled  by  nature  for  many  agricultural  purposes. 

The  surface  soil,  o to  6^3  inches,  is  a yellow  silt  loam  varying  to  a gray- 
ish yellow.  The  freshly  plowed  soil  appears  yellow  or  brownish  yellow,  but 
when  it  becomes  dry  after  a rain  it  is  of  a grayish  color.  The  organic-matter 
content  is  quite  low,  averaging  only  2.05  percent,  or  20 Y2.  tons  in  the  plowed 
soil  of  an  acre. 

The  subsurface  varies  from  a yellow  silt  loam  to  a yellow  clayey  silt  loam, 
and  contains  only  about  15  tons  of  organic  matter  per  acre  of  4 million 
pounds,  the  amount  diminishing  with  depth.  The  thickness  of  this  stratum 
varies  from  2 to  12  inches,  depending  on  the  amount  of  recent  erosion. 

The  subsoil  consists  of  a yellow  clayey  silt. 

Owing  to  erosion,  this  type  varies  greatly.'  Glacial  drift  is  frequently 
exposed  on  the  surface.  In  some  cases  it  forms  both  subsurface  and  subsoil, 
while  in  others  it  constitutes  all  or  part  of  the  subsoil,  or  it  may  even  be 
found  only  below  40  inches. 

The  first  and  most  important  thing  in  the  management  of  this  soil  is  to 
prevent  erosion,  which  may  occur  either  by  sheet  washing  or  by  gullying. 


La  Salle  County 


1913] 

On  uniform  slopes  sheet  washing  does  the  greater  damage,  but  on  the  irregu- 
lar slopes  found  in  this  county  both  forms  do  great  damage.  Many  of  the 
slopes  are  too  steep  to  permit  of  cultivation,  and  they  ought  not  to  be  cleared 
of  the  protecting  forest.  Most  of  this  type  is  in  forest  or  pasture,  and  should 
never  be  cultivated,  for,  if  broken  up,  erosion  would  shortly  ruin  the  land  for 
all  purposes.  (For  methods  of  preventing  erosion  of  soils  see  Circular  119.) 

The  only  general  soil  treatment  recommended  for  this  type  is  the  use  of 
ground  limestone  either  when  preparing  the  land  for  seeding  to  legume  crops 
or  as  a top-dressing  on  pastures  to  encourage  the  growth  of  clovers  in  the 
pasture  herbage.  Where  the  slope  is  not  too  steep,  alfalfa  may  sometimes  be 
grown  to  advantage.  In  getting  this  crop  started,  500  pounds  per  acre  of 
steamed  bone  meal  or  acid  phosphate  may  well  be  plowed  under  with  farm 
manure,  and  then  5 tons  per  acre  of  ground  limestone  should  be  applied  be- 
fore preparing  the  seed  bed,  which  of  course,  ought  to  be  well  inoculated  with 
soil  from  an  old  alfalfa  field  or  sweet-clover  patch.  (See  Circular  86, 
“Science  and  Sense  in  the  Inoculation  of  Legumes.”) 

Rock  Outcrop  (1199) 

This  type  consists  of  rock  ledges  and  some  uncovered  rock  surfaces,  prin- 
cipally in  the  Illinois-river  valley  from  Utica  east.  The  rock  is  nearly  all 
St.  Peters  sandstone,  with  some  magnesian  limestone  in  the  vicinity  of 
La  Salle  and  Utica  that  is  used  for  cement.  A shaley  sandstone  is  exposed 
in  the  Illinois-river  valley  near  Seneca  that  gives  rise  to  a residual  type  of 
soil  in  that  region. 

(c)  Terrace  Soils 

These  consist  of  soils  formed  on  terraces,  or  benches,  in  valleys.  The  ter- 
races owe  their  formation  generally  to  the  deposition  of  material  from  an 
overloaded  stream  during  the  melting  of  the  glaciers.  In  this  way  valleys 
were  partly  filled.  Later  these  streams  cut  down  thru  these  fills  and  de- 
veloped new  bottom  lands  or  flood  plains  at  a lower  level,  leaving  part  of  the 
old  fill  as  a terrace.  The  lowest  and  most  recently  formed  bottom  land  is 
called  first  bottom.  The  material  filling  the  valleys  may  be  coarse  or  fine. 
That  forming  the  terraces  in  the  Vermilion  valley,  Indian  creek,  and  in  part 
in  the  Illinois-river  valley,  is  mostly  silt,  while  in  the  Fox-river  valley  it  is 
sand  and  gravel.  Part  of  the  terrace  of  the  Illinois-river  valley  seems  to  be 
the  stony  floor  of  the  valley  covered  from  a few  inches  to  several  feet  with 
fine  material  that  now  forms  the  soil.  In  many  cases  this  material  is  partly 
of  residual  origin.  (The  series  number  for  the  terrace  soils  is  1500.) 

Brozm  Silt  Loam  (1526) 

This  type  occurs  only  in  the  Illinois-river  valley.  Owing  to  its  method 
of  formation,  it  is  somewhat  variable.  The  material  is  derived  both  from 
sediment  deposited  by  the  Illinois  river  at  a former  period  and  by  small 
streams  from  the  upland.  The  older  material  is  characterized  by  a much 
darker  color  and  heavier  texture,  while  the  newer  deposit  brought  down  by 
small  streams  is  usually  lighter  in  color  as  well  as  coarser  in  texture.  This 
type  is  not  generally  well  drained,  and  in  many  areas  thoro  drainage  is  the 
first  essential.  As  a rule,  it  lies  sufficiently  above  the  Illinois  river  to  allow 
of  good  drainage. 

The  total  area  of  this  type  is  10.26  square  miles,  or  6,566  acres,  and 
comprises  .88  percent  of  the  entire  area  of  the  county. 


28 


Soil  Report  No.  5 


[July, 


The  surface  soil,  o to  6^5  inches,  varies  from  a light  brown  silt  loam  to 
a dark  brown  clayey  silt  loam,  the  heavier  phase  predominating.  Locally, 
even  some  black  clay  loam  is  found,  also  small  areas  of  muck  or  shallow 
peat,  with  their  characteristic  surface  soils,  while  in  places  the  surface  soil 
contains  a considerable  percentage  of  gravel.  These  local  variations  are  in 
too  small  areas  to  be  shown  on  the  map. 

The  subsurface  soil  varies  from  a brown  to  a black  silt  loam  or  clay  loam 
extending  to  a depth  of  from  16  to  25  inches. 

The  subsoil  varies  from  a yellow  plastic  clayey  silt  to  a drab  clay,  the  lat- 
ter usually  occurring  in  the  areas  originally  poorly  drained. 

The  different  strata  of  this  type  are  sufficiently  pervious  to  permit  good 
drainage,  and  drainage  is  a matter  of  first  importance.  The  organic  matter 
should  be  maintained,  and  even  increased  in  the  lighter  phases.  The  type  is 
exceedingly  rich  in  potassium  and  limestone  (especially  in  the  subsurface 
and  subsoil),  but  the  addition  of  phosphorus  will  be  necessary  if  its  pro- 
ductive power  is  to  be  maintained  at  a high  point. 

Brown  Silt  Loam  on  Gravel  (1526.4) 

The  total  area  of  this  type  in  the  county  is  83.2  acres.  As  an  average, 
the  gravel  is  about  22  inches  below  the  surface.  This  provides  excellent 
drainage, — in  fact,  too  good  for  seasons  when  the  crop  is  likely  to  suffer 
from  lack  of  moisture. 

The  surface  soil,  o to  6%  inches,  is  a brown  silt 'loam  containing  a per- 
ceptible amount  of  sand. 

The  subsurface,  62/z  to  16  or  18  inches,  is  a light  brown  silt  loam  becom- 
ing lighter  with  depth. 

The  subsoil  is  composed  chiefly  of  gravel,  but  it  may  have  some  silty 
material  overlying  the  gravel.  The  comparatively  thin  stratum  of  fine  ma- 
terial does  not  furnish  a sufficient  reservoir  for  the  moisture  necessary  for 
crop  use  unless  rains  are  frequent. 

While  this  type  is  not  markedly  acid,  it  is  devoid  of  limestone  even  to  a 
depth  of  40  inches.  Organic  manures,  phosphorus,  and  limestone  are  all  re- 
quired for  the  improvement  and  maintenance  of  its  fertility. 

Brown  Silt  Loam  on  Rock  (1526.5) 

This  type  occupies  only  38.4  acres  and  lies  in  one  area  in  the  Illinois-river 
valley  east  of  Ottawa.  It  is  rather  poorly  drained.  The  surface  soil  is  a 
brown  to  black  slightly  clayey  silt  loam,  while  the  subsurface  is  somewhat 
heavier.  On  the  whole,  this  is  one  of  the  richest  soils  found  in  Illinois,  It 
is  about  twice  as  rich  in  nitrogen  and  four  times  as  rich  in  phosphorus  as 
the  common  corn-belt  prairie  land.  The  rocks,  which  are  not  always  covered 
by  the  soil,  consist  of  boulders  and  not  bed  rock,  and  consequently  the  sub- 
soil may  absorb  and  retain  moisture  fairly  well.  It  is  suggested  that  this 
area  may  once  have  been  the  roosting  place  for  wild  water  fowls  or  other 
birds,  and  that  the  exceptional  richness  of  the  soil  may  be  due  to  the  accumu- 
lated droppings  and  decomposed  feathers  and  skeletons  of  the  birds.  Much 
of  the  area  can  be  used  only  for  pasture  because  of  the  numerous  boulders, 
many  of  which  lie  near  the  surface  while  some  rise  above  it. 


I9i3\ 


La  Salle  County 


29 


Brown  Silt  Loam  over  Gravel  (1527) 

This  type  aggregates  5.12  square  miles,  or  3,277  acres.  It  occurs  in  large 
areas  along  the  Fox  river  and  lies  on  part  of  the  old  gravel  fill  of  that  valley. 
As  a rule,  the  type  is  well  drained,  owing  to  the  pervious  character  of  the 
subsoil.  The  topography  is  undulating,  due  to  erosion  and  the  action  of  wind 
in  piling  up  silt  and  sand. 

The  surface  soil,  o to  &/$  inches,  is  a brown  silt  loam,  the  color  varying 
with  the  topography  and  drainage. 

The  subsurface  soil,  6^3  to  18  inches,  is  a light  brown  silt  loam  underlain 
by  a yellow  silt  subsoil.  Locally  this  type  has  a perceptible  amount  of  sand. 

This  type  is  rich  only  in  potassium,  and  requires  for  its  improvement 
limestone,  organic  manures,  and  phosphorus. 

Yellow-Gray  Silt  Loam  on  Gravel  (1534.4) 

A small  area  of  this  type,  12.8  acres,  occurs  in  Sections  35  and  36,  Town- 
ship 35  North,  Range  4 East.  The  surface  soil  is  a light  grayish  yellow  silt 
loam  containing  2.5  percent  of  organic  matter,  while  the  subsurface  soil  con- 
tains .8  percent.  Gravel  occurs  commonly  at  a depth  of  18  to  24  inches. 

The  analysis  shows  the  need  of  organic  manures,  phosphorus,  and  lime- 
stone. 

Yellozv-Gray  Silt  Loam  over  Gravel  (1536) 

This  type  is  found  to  some  extent  along  the  larger  streams,  but  especially 
along  the  Fox  river.  It  covers  a total  area  of  6.68  square  miles,  or  4,275 
acres,  a trifle  over  percent  of  the  total  area  of  the  county.  The  topog- 
raphy varies  somewhat,  erosion  and  wind  action  having  produced  a gently 
rolling  or  undulating  surface. 

The  surface  soil  varies  from  a grayish  yellow  to  a yellow  silt  loam.  Sand 
in  perceptible  amounts  is  almost  invariably  present.  The  organic-matter 
content  amounts  to  2.5  percent,  or  25  tons  per  acre. 

The  subsurface  soil,  6^$  to  16  inches,  is  a yellow  to  grayish  yellow  silt 
loam  containing  about  .7  percent  of  organic  matter. 

The  subsoil  is  a yellow  pulverulent  silt. 

For  a silt  loam,  this  type  is  poor  in  organic  matter  and  phosphorus,  and 
it  is  acid  even  to  a depth  of  40  inches,  so  that,  in  addition  to  organic  matter 
and  phosphorus,  limestone  should  be  supplied. 

Brown  Sandy  Loam  (1560) 

This  type  covers  only  4.80  square  miles,  or  3,072  acres,  and  occurs  en- 
tirely along  the  Fox  and  Illinois  rivers.  Its  height  above  the  river  varies 
somewhat,  being  so  low  in  some  places  as  to  be  subject  to  overflow  during 
extremely  high  water.  It  is  generally  well  drained,  altho  in  some  small  areas 
the  difficulty  of  securing  a proper  outlet  renders  it  too  wet. 

The  surface  soil,  o to  6%  inches,  is  a brown  sandy  loam,  the  color  vary- 
ing with  the  drainage.  The  sand  is  mostly  coarse.  Much  of  it  in  the  Illinois- 
river  valley  is  probably  derived  from  the  sandstone  in  the  immediate  vicinity. 

Owing  to  its  physical  composition,  this  type  is  easy  to  work  and  to  keep 
in  good  tilth. 

The  subsurface  soil,  62/z  to  about  20  inches,  is  a brown  sandy  loam,  the 
color  becoming  lighter  with  depth.  This  is  underlain  with  a yellow  or  brown- 


30 


Soil  Report  No.  5 


[July, 


ish  yellow  subsoil  that  varies  from  a sandy  loam  to  a sand.  In  some  cases 
this  latter  is  probably  residual  sand.  At  lower  depths  gravel  is  sometimes 
found ; indeed  at  Sheridan  large  quantities  are  being  taken  from  this  type  of 
terrace  soil. 

Considering  its  deep  feeding  range,  this  sandy  loam  is  well  supplied  with 
phosphorus.  Limestone  and  organic  manures  are  the  materials  most  needed 
for  its  improvement,  and  it  is  not  unlikely  that  potassium  could  be  used  with 
profit.  While  the  total  supply  of  potassium  is  large,  most  of  it  is  locked  up 
in  medium  or  coarse  sand  grains.  To  obtain  the  best  and  most  profitable 
results  on  such  soils,  the  use  of  potassium  is  usually  required,  altho  very 
marked  improvement  can  be  made  with  limestone  and  legume  crops ; and,  if 
all  coarse  products  are  returned  to  the  soil  either  directly  or  in  manure,  with- 
out loss  by  leaching,  the  necessity  for  purchasing  potassium  will  be  greatly 
reduced. 


Brown  Sandy  Loam  on  Gravel  (1560.4) 

This  type  occupies  an  area  of  192  acres  in  the  valley  of  the  Illinois  river 
near  Seneca.  It  is  rather  variable  both  as  to  the  amount  of  sand  it  contains 
and  the  depth  to  the  gravel  beneath  the  surface. 

The  surface  stratum,  o to  62/$  inches,  is  a brown  sandy  loam,  with  2.2 
percent  organic  matter,  while  the  subsurface  is  lighter  in  color,  containing 
1.2  percent  of  organic  matter.  The  depth  to  gravel  varies  from  12  to  30 
inches. 

This  type  is  well  supplied  with  phosphorus  but  is  poor  in  organic  matter 
and,  altho  nearly  neutral,  contains  no  limestone.  The  use  of  potassium  in 
addition  to  limestone  and  organic  manures  may  prove  profitable,  especially  if 
much  potassium  is  carried  away  in  the  products  sold  from  the  farm. 

Brown  Sandy  Loam  on  Rock  (1560.5) 

This  type  occurs  only  in  the  Illinois-river  valley  and  represents  the  rock 
of  the  old  river  bed  that  has  become  covered  with  sandy  material  either  thru 
deposition  from  water  or  wind  or  thru  disintegration  of  the  underlying  sand- 
stone by  weathering  agencies.  This  material  has  become  mixed  with  more 
or  less  organic  matter,  thus  forming  a soil.  The  area  covered  is  5.73  square 
miles,  or  3,667  acres,  a little  less  than  percent  of  the  entire  area  of  the 
county.  The  depth  to  the  rock  varies  from  12  to  30  inches. 

The  surface  soil,  o to  6^3  inches,  is  a brown  sandy  loam,  with  a variable 
quantity  of  sand  and  4.55  percent,  or  60  tons  per  acre,  of  organic  matter. 

The  subsurface  varies  from  a sandy  loam  to  a sand,  the  latter  being  de- 
rived from  the  sandstone  underlying  it. 

This  type  is  not  of  great  value  agriculturally  because  of  the  proximity  of 
the  rock  to  the  surface,  which  renders  it  a poor  soil  to  resist  either  drouth  or 
excessive  rainfall,  altho  the  crops  suffer  less  from  the  latter  than  from  the 
former.  Much  of  it  is  not  under  cultivation.  Liberal  use  should  be  made  of 
legumes  and  organic  manures ; and  both  the  physical  and  the  chemical  com- 
positions indicate  that  potassium  should  be  applied  for  the  best  results.  The 
soil  still  contains  a fair  amount  of  humus  and  limestone;  and,  for  a sandy 
loam,  the  phosphorus  supply  is  very  satisfactory,  altho,  where  the  depth  of 
soil  is  too  restricted,  additional  phosphorus  may  be  needed  if  the  improve- 
ment of  such  shallow  soil  is  attempted.  This,  however,  is  scarcely  to  be  ad- 


La  Salle  County 


31 


1913 ] 


vised,  unless  for  special  crops  and  with  provision  to  supplement  the  rainfall 
by  irrigation  when  necessary.  The  narrow  ratio  between  the  nitrogen  and 
the  organic  carbon  indicates  that  the  organic  matter  consists  largely  of  old 
plant  residues  resistant  to  decay. 

Yellow-Gray  Sandy  Loam  (1564) 

This  type  covers  less  than  10  acres  of  land.  The  surface  is  a yellowish 
gray  sandy  loam.  The  soil  is  very  poor  in  nitrogen  and  organic  matter,  and 
the  supply  of  limestone  is  limited,  the  subsurface  and  subsoil  being  acid.  Lib- 
eral use  of  these  materials  should  effect  enormous  improvement ; indeed  with 
the  deep  feeding  range  afforded  plants,  and  the  amount  of  phosphorus  and 
potassium  in  the  lower  strata,  it  is  doubtful  if  anything  more  than  limestone 
and  organic  manures  can  be  used  with  profit  in  good  systems  of  farming. 


Dune  Sand  (1581) 

This  type  occupies  only  25  acres,  a part  of  which  is  in  the  Fox-river  valley 
and  the  rest  in  the  Illinois-river  valley  south  of  the  river  and  west  of  Ottawa. 
It  has  the  characteristic  dune  topography.  The  surface  soil  is  a slightly  loamy 
sand,  with  less  than  1 percent  of  organic  matter,  underlain  by  a uniformly 
yellowish  sand  of  medium  texture.  Only  limestone  and  organic  manures  are 
needed  to  markedly  improve  this  soil,  but  for  the  highest  and  most  profitable 
improvement  potassium  and  phosphorus  may  also  need  to  be  supplied,  and 
probably  in  the  order  named. 

Gravelly  Loam  (1590) 

This  type  occurs  in  the  Illinois-river  valley  west  of  Ottawa  on  both  sides 
of  the  river,  the  gravel  north  of  the  river  being  the  coarser.  It  occupies  an 
area  of  300  acres,  and  is  undulating  in  topography. 

The  surface  soil,  o to  6^  inches,  is  a mixture  of  gravel,  sand,  and  a 
small  amount  of  the  finer  constituents,  together  with  5.56  percent  of  organic 
matter,  or  74  tons  per  acre. 

The  subsurface  resembles  the  surface  but  contains  less  organic  matter. 
The  gravel  becomes  so  large  and  abundant  at  a depth  of  15  to  24  inches  that 
sampling  with  the  soil  auger  is  impracticable. 

This  is  a moderately  rich  soil  and  ought  to  grow  alfalfa,  grapes,  or  other 
crops  that  are  adapted  to  the  soil  and  topography.  With  a liberal  use  of 
legume  crops  or  organic  manure,  potassium  is  the  only  addition  likely  to 
prove  profitable,  most  of  this  element  being  locked  up  in  the  coarse  sand  and 
gravel. 

(d)  Swamp  and  Bottom-Land  Soils 
Deep  Brown  Silt  Loam  (1426) 

The  Illinois  river  below  a point  about  halfway  between  Utica  and  La  Salle 
has  developed  a wide,  level  flood-plain  extending  to  the  west  side  of  the 
county,  while  the  flood-plain  to  the  eastward  is  narrower  and  less  conspicuous 
and  in  some  places  absent  entirely.  The  deposition  of  sediment  on  this  over- 
flowed land  has  formed  the  deep  brown  silt  loam  of  the  bottom  land.  As' 
a rule,  it  is  low  and  rather  poorly  drained,  with  flat  to  slightly  undulating 
topography. 

The  surface  soil,  o to  inches,  is  a brown,  somewhat-clayey  silt  loam 


32 


Soil  Report  No.  5 


[July, 


containing  4.42  percent  of  organic  matter,  or  44  tons  per  acre.  It  varies 
somewhat  from  this  composition,  in  places  being  sufficiently  sandy  to  modify 
the  texture  to  a considerable  extent. 

The  subsurface  and  subsoil  vary  but  little  from  the  surface,  containing 
4.27  percent  and  4 percent,  respectively,  of  organic  matter. 

This  is  a rich,  deep  soil,  and  its  fertility  is  usually  well  maintained  by  the 
sediments  deposited  from  overflow,  including  some  sewage  received  from  the 
city  of  Chicago.  It  is  exceedingly  fertile,  and  crops  grow  upon  it  with  re- 
markable rapidity. 

A thoroly  adequate  system  of  underdrainage  which  will  quickly  remove 
the  surplus  soil  water  would  be  of  great  assistance  in  getting  the  land  into 
condition  for  planting  as  soon  as  possible  after  the  usual  spring  overflow.  It 
is  by  no  means  certain,  however,  that  permanent  protection  from  overflow 
with  its  usual  enriching  deposit,  would  result  in  a larger  aggregate  of  crops 
produced  during  a long  series  of  years,  provided  the  normal  level  of  the  water 
is  not  too  near  the  surface  of  the  land. 

Deep  Peat  (1401) 

This  type  is  found  exclusively  in  the  Illinois-river  valley,  with  the  excep- 
tion of  a small  area  in  Section  27,  east  of  Tonica,  and  occupies  a total  area 
of  364  acres.  The  peat  in  the  Illinois  valley  is  found  generally  in  the  lower 
and  more  poorly  drained  areas  near  the  bluff  and  where  the  land  receives 
water  either  from  springs  or  from  surface  drainage  from  higher  land.  This 
has  brought  about  conditions  favorable  for  the  growth  and  preservation  of 
peat-forming  grasses,  sedges,  and  mosses,  whose  partly-decayed  products  have 
accumulated  until  a deposit  of  peat  30  inches  or  more  in  depth  has  formed. 
Much  of  this  is  still  a swamp  and  is  utilized,  if  at  all,  only  for  hay. 

Owing  to  the  origin  of  this  type,  there  is  generally  not  much  difference 
between  the  strata. 

The  surface  soil,  o to  6 2/t,  inches,  is  a brown  peat  varying  somewhat  in  the 
different  areas  on  account  of  the  amount  of  decomposition  from  overflow. 
The  one  composite  sample  collected  from  this  stratum  contained  30.6  percent 
of  organic  matter,  but  in  some  areas  the  amount  is  doubtless  still  higher. 

The  subsurface  soil  is  a brown,  undecomposed  peat,  showing  47.12  per- 
cent of  organic  matter  in  the  sample  collected.  The  subsoil  changes  but  little 
to  a depth  of  40  inches. 

Drainage  is  the  first  requirement  of  this  type.  A trial  application  of  potas- 
sium is  recommended;  and,  with  continued  cropping,  applications  of  phos- 
phorus may  also  become  profitable.  (See  Illinois  Bulletin  157,  “Peaty  Swamp 
Lands.”) 

Medium  Peat  on  Clay  (1402) 

This  type  is  represented  by  an  area  of  about  83  acres  east  of  Tonica  in 
Section  27.  It  occupies  a depression  in  the  center  of  which  is  an  area  of  deep 
peat  with  the  medium  peat  surrounding  it.  This  area  has  been  drained  and 
is  under  cultivation. 

The  surface  stratum,  o to  inches,  is  a dark  brown  peat  containing 
36. 1 percent  of  organic  matter  so  thoroly  decomposed  as  to  have  lost  all  traces 
of  vegetable  tissue. 

The  subsurface  is  a black,  decomposed  peat  lying  upon  a drab  clay  16  to 
20  inches  below  the  surface. 


La  Salle  County 


33 


W3] 


If  this  soil  does  not  produce  good  crops  when  well  drained,  the  remedy  is 
likely  to  be  found  in  deep  plowing.  If  necessary,  one  plow  should  follow  an- 
other in  the  same  furrow  in  order  to  reach  the  clay  (which  is  rich  in  potas- 
sium) and  mix  it  with  the  more  peaty  top  soil,  as  more  fully  explained  in 
Bulletin  157. 

(e)  Residual  Soils 

This  class  of  soils  is  formed  by  the  accumulation  of  the  loose  material 
resulting  from  the  weathering  of  rocks  in  place.  Very  little  of  this  class  ex- 
ists in  Illinois,  owing  to  the  action  of  the  glaciers  in  removing  and  covering 
up  the  residual  material  by  glacial  drift,  or  boulder  clay.  La  Salle  county 
probably  has  the  largest  area  of  residual  soil  found  in  the  state. 

Brozvn  Sandy  Loam  on  Rock  (060.5) 

This  type  covers  2.38  square  miles,  or  1523  acres.  It  is  formed  from  the 
disintegration  of  a shaly  sandstone,  and  is  found  only  in  the  valley  of  the 
Illinois  river  where  the  drift  has  been  removed  by  the  stream.  The  process 
of  disintegration  has  produced  from  12  to  30  inches  of  loose  material  which 
forms  the  soil. 

The  surface  soil,  o to  6^3  inches,  is  a Tight  brown  sandy  loam  varying  to 
a yellowish  brown.  It  contains  many  small  pieces  of  the  shaly  sandstone, 
usually  not  over  an  inch  or  two  in  diameter  and  inch  thick.  It  contains 
2.27  percent  of  organic  matter,  or  30  tons  per  acre. 

The  subsurface  soil  is  a yellow  to  brownish  yellow  sandy  loam.  Rock  is 
found  12  to  30  inches  below  the  surface.  The  proximity  of  the  rock  to  the 
surface  makes  the  crops  growing  on  this  type  very  subject  to  drouth  or  to 
excessive  moisture.  Drainage  is  at  once  very  essential  and  extremely  difficult. 

This  type  is  poor  in  organic  matter  and  contains  no  limestone ; both  these 
materials  should  be  provided  for  its  improvement.  Considering  its  shallow 
character  and  coarse  texture,  we  may  expect  that  both  phosphorus  and  potas- 
sium will  be  required  for  its  most  marked  improvement,  and  irrigation  may 
also  be  needed;  but  so  much  expense  as  this  would  entail  is  justified  only  for 
intensive  cropping. 

Residual  Sand  (083) 

This  type  is  formed  from  the  disintegration  of  the  St.  Peters  sandstone 
and  has  no  particular  agricultural  value.  None  of  it  is  under  cultivation,  but 
it  carries  a rather  stunted  growth  of  timber.  The  type  covers  70  acres  and, 
in  addition,  some  small  areas  along  the  bluffs  of  the  Illinois  river  not  large 
enough  to  map.  The  surface  for  about  2 inches  is  a slightly  loamy  sand  and 
then  passes  into  a yellow  sand  which  continues  to  within  a few  inches  of  the 
sand  rock,  where  a white  sand  is  encountered.  The  topography  is  very  rolling. 

In  plant-food  content  this  residual  sand  is  the  poorest  soil  thus  far  found 
in  Illinois.  While  the  top  soil  was  found  to  contain  about  2 tons  of  limestone 
per  acre,  this  was  evidently  due  to  some  surface  addition,  for  the  subsurface 
and  subsoil  contain  no  lime. 

To  produce  satisfactory  crops  upon  this  soil,  liberal  use  should  be  made 
of  organic  manures,  phosphorus,  potassium,  and  dolomitic  limestone,  the  lat- 
ter supplying  calcium  and  magnesium.  Provision  should  also  be  made  for 
irrigation  as  a means  of  protection  during  even  short  periods  of  drouth, 
especially  where  the  bed  rock  is  only  2 or  3 feet  below  the  surface.  Such 
complete  treatment  would  not  be  practical  except  possibly  in  gardening. 


34 


Soil  Report  No.  5 


l July, 


APPENDIX 

A study  of  the  soil  map  and  the  tabular  statements  concerning  crop  re- 
quirements, the  plant-food  content  of  the  different  soil  types,  and  the  actual 
results  secured  from  definite  field  trials  with  different  methods  or  systems 
of  soil  improvement,  and  a careful  study  of  the  discussion  of  general  prin- 
ciples and  of  the  descriptions  of  individual  soil-  types,  will  furnish  the  most 
necessary  and  useful  information  for  the  practical  improvement  and  perma- 
nent preservation  of  the  productive  power  of  every  kind  of  soil  on  every 
farm  in  the  county. 

More  complete  information  concerning  the  most  extensive  and  impor- 
tant soil  types  in  the  great  soil  areas  in  all  parts  of  Illinois  is  contained  in 
Bulletin  123,  “The  Fertility  in  Illinois  Soils,”  which  contains  a colored  gen- 
eral survey  soil  map  of  the  entire  state. 

Other  publications  of  general  interest  are: 

Bulletin  No.  76,  “Alfalfa  on  Illinois  Soils” 

Bulletin  No.  94,  “Nitrogen  Bacteria  and  Legumes” 

Bulletin  No.  115,  “Soil  Improvement  for  the  Worn  Hill  Lands  of  Illinois” 

Bulletin  No.  125,  “Thirty  Years  of  Crop  Rotation  on  the  Common  Prairie  Lands  of 
Illinois” 

Circular  No.  no,  “Ground  Limestone  for  Acid  Soils” 

Circular  No.  .127,  “Shall  we  use  Natural  Rock  Phosphate  or  Manufactured  Acid  Phos- 
phate for  the  Permanent  Improvement  of  Illinois  Soils?” 

Circular  No.  129,  “The  Use  of  Commercial  Fertilizers” 

Circular  No.  149,  “Some  Results  of  Scientific  Soil  Treatment”  and  “Methods  and  Re- 
sults of  Ten  Years’  Soil  Investigation  in  Illinois” 

Circular  No.  165,  “Shall  we  use  ‘Complete’  Commercial  Fertilizers  in  the  Corn  Belt?” 

NOTE. — Information  as  to  where  to  obtain  limestone,  phosphate,  bone  meal,  and  po- 
tassium salts,  methods  of  application,  etc.,  will  also  be  found  in  Circulars  no  and  165. 

Soil  Survey  Methods 

The  detail  soil  survey  of  a county  consists  essentially  of  indicating  on 
a map  the  location  and  extent  of  the  different  soil  types;  and,  since  the 
value  of  the  survey  depends  upon  its  accuracy,  every  reasonable  means  is 
employed  to  make  it  trustworthy.  To  accomplish  this  object  three  things 
are  essential : first,  careful,  well-trained  men  to  do  the  work ; second,  an  ac- 
curate base  map  upon  which  to  show  the  results  of  their  work:  and,  third, 
the  means  necessary  to  enable  the  men  to  place  the  soil-type  boundaries, 
streams,  etc.,  accurately  upon  the  map. 

The  men  selected  for  the  work  must  be  able  to  keep  their  location 
exactly  and  to  recognize  the  different  soil  types,  with  their  principal  varia- 
tions and  limits,  and  they  must  show  these  upon  the  maps  correctly.  A 
definite  system  is  employed  in  checking  up  this  work.  As  an  illustration,  one 
soil  expert  will  survey  and  map  a strip  80  rods  or  160  rods  wide  and  any 
convenient  length,  while  his  associate  will  work  independently  on  another 
strip  adjoining  this  area,  and,  if  the  work  is  correctly  done,  the  soil  type 
boundaries  will  match  up' on  the  line  between  the  two  strips. 

An  accurate  base  map  for  field  use  is  absolutely  necessary  for  soil  map- 
ping. The  base  maps  are  made  on  a scale  of  one  inch  to  the  mile.  The 
official  data  of  the  original  or  subsequent  land  survey  are  used  as  a basis  in 
the  construction  of  these  maps,  while  the  most  trustworthy  county  map  avail- 
able is  used  in  locating  temporarily  the  streams,  roads,  and  railroads,  Since 
the  best  of  these  published  maps  have  some  inaccuracies,  the  location  of  every 
road,  stream,  and  railroad  must  be  verified  by  the  soil  surveyors,  and  cor- 


La  Salle  County 


35 


*913] 


rected  if  wrongly  located.  In  order  to  make  these  verifications  and  correc- 
tions, each  survey  party  is  provided  with  an  odometer  for  measuring  dis- 
tances, and  a plane  table  for  determining  directions  of  roads,  railroads,  etc. 

Each  surveyor  is  provided  with  a base  map  of  the  proper  scale,  which  is 
carried  with  him  in  the  field ; and  the  soil-type  boundaries,  additional  streams, 
and  necessary  corrections  are  placed  in  their  proper  locations  upon  the  map 
while  the  mapper  is  on  the  area.  Each  section,  or  square  mile,  is  divided  into 
40-acre  plots  on  the  map,  and  the  surveyor  must  inspect  every  ten  acres  and 
determine  the  type  or  types  of  soil  composing  it.  The  different  types  are 
indicated  on  the  map  by  different  colors,  pencils  being  carried  in  the  field 
for  this  purpose.  . 

A small  auger  40  inches  long  forms  for  each  man  an  invaluable  tool  with 
which  he  can  quickly  secure  samples  of  the  different  strata  for  inspection. 
An  extension  for  making  the  auger  80  inches  long  is  taken  by  each  party, 
so  that  any  peculiarity  of  the  deeper  subsoil  layers  may  be  studied.  Each 
man  carries  a compass  to  aid  in  keeping  directions.  Distances  along  roads 
are  measured  by  an  odometer  attached  to  the  axle  of  the  vehicle,  while  dis- 
tances in  the  field  off  the  roads  are  determined  by  pacing,  an  art  in  which 
the  men  become  expert  by  practice.  The  soil  boundaries  can  thus  be  located 
with  as  high  a degree  of  accuracy  as  can  be  indicated  by  pencil  on  the 
scale  of  one  inch  to  the  mile. 


Soil  Characteristics 


The  unit  in  the  soil  survey  is  the  soil  type,  and  each  type  possesses  more 
or  less  definite  characteristics.  The  line  of  separation  between  adjoining 
types  is  usually  distinct,  but  sometimes  one  type  grades  into  another  so 
gradually  that  it  is  very  difficult  to  draw  the  line  between  them.  In  such 
exceptional  cases,  some  slight  variation  in  the  location  of  soil-type  boundaries 
is  unavoidable. 

Several  factors  must  be  taken  into  account  in  establishing  soil  types. 
These  are  (i)'the  geological  origin  of  the  soil,  whether  residual,  glacial, 
loessial,  alluvial,  colluvial,  or  cumulose;  (2)  the  topography,  or  lay  of  the 
land ; (3)  the  native  vegetation,  as  forest  or  prairie  grasses;  (4)  the  structure, 
or  the  depth  and  character  of  the  surface,  subsurface,  and  subsoil;  (5)  the 
physical,  or  mechanical,  composition  of  the  different  strata  composing  the  soil, 
as  the  percentages  of  gravel,  sand,  silt,  clay,  and  organic  matter  which  they 
contain;  (6)  the  texture,  or  porosity,  granulation,  friability,  plasticity,  etc.; 
(7)  the  color  of  the  strata;  (8)  the  natural  drainage;  (9)  agricultural 
value,  based  upon  its  natural  productiveness;  (10)  the  ultimate  chemical 
composition  and  reaction. 

The  common  soil  constituents  are  indicated  in  the  following  outline : 
Constituents  of  Soils 


Soil 

Constituents 


Organic 

Matter 


Inorganic 

Matter 


f Comprising  undecomposed  and  partially  decayed 
1 vegetable  material 


Clay 

mm. 

1 and 

less 

Silt 

mm. 

to  .03 

mm. 

Sand 

03 

mm. 

to  1. 

mm. 

Gravel 

mm. 

to  32 

mm. 

Stones 

32 

. mm 

1.  and 

over 

*25  millimeters  equal  1 inch. 

Further  discussion  of  these  constituents  is  given  in  Circular  82. 


36 


Soil  Report  No.  5 


Uuly, 


Groups  op  Soil  Types 

The  following  gives  the  different  general  groups  of  soils: 

Peats — Consisting  of  35  percent  or  more  of  organic  matter,  sometimes 
mixed  with  more  or  less  sand  or  silt. 

Peaty  loams — 15  to  35  percent  of  organic  matter  mixed  with  much  sand 
and  silt  and  a little  clay. 

Mucks — 15  to  35  percent  of  partly  decomposed  organic  matter  mixed 
with  much  clay  and  some  silt. 

Clays — Soils  with  more  than  25  percent  of  clay,  usually  mixed  with  much 
silt. 

Clay  loams — Soils  with  from  15  to  25  percent  of  clay,  usually  mixed 
with  much  silt  and  some  sand.  • 

Silt  loams — Soils  with  more  than  50  percent  of  silt  and  less  than  15 
percent  of  clay,  mixed  with  some  sand. 

Loams — Soils  with  from  30  to  50  percent  of  sand  mixed  with  much  silt 
and  a little  clay. 

Sandy  loams — Soils  with  from  50  to  75  percent  of  sand. 

Fine  sandy  loams — Soils  with  from  50  to  75  percent  of  fine  sand  mixed 
with  much  silt  and  little  clay. 

Sands — Soils  with  more  than  75  percent  of  sand. 

Gravelly  loams — Soils  with  15  to  50  percent  of  gravel  with  much  sand 
and  some  silt. 

Gravels — Soils  with  more  than  50  percent  of  gravel. 

Stony  loams — Soils  containing  a considerable  number  of  stones  over  one 
inch  in  diameter. 

Rock  outcrop — Usually  ledges  of  rock  having  no  agricultural  value. 

More  or  less  organic  matter  is  found  in  nearly  all  the  above  classes. 

Supply  and  Liberation  of  Plant  Food 

The  productive  capacity  of  land  in  humid  sections  depends  almost  wholly 
upon  the  power  of  the  soil  to  feed  the  crop;  and  this,  in  turn,  depends  both 
upon  the  stock  of  plant  food  contained  in  the  soil  and  upon  the  rate  at  which 
this  is  liberated,  or  rendered  soluble  and  available  for  use  in  plant  growth. 
Protection  from  weeds,  insects,  and  fungous  diseases,  tho  exceedingly  im- 
portant, is  not  a positive  but  a negative  factor  in  crop  production. 

The  chemical  analysis  of  the  soil  gives  the  invoice  of  fertility  actually 
present  in  the  soil  strata  sampled  and  analyzed,  but  the  rate  of  liberation  is 
governed  by  many  factors,  some  of  which  may  be  controlled  by  the  farmer, 
while  others  are  largely  beyond  his  control.  Chief  among  the  important 
controllable  factors  which  influence  the  liberation  of  plant  food  are  lime- 
stone and  decaying  organic  matter,  which  may  be  added  to  the  soil  by  direct 
application  of  ground  limestone  and  farm  manure.  Organic  matter  may  be 
supplied  also  by  green-manure  crops  and  crop  residues,  such  as  clover,  cow- 
peas,  straw,  and  cornstalks.  The  rate  of  decay  of  organic  matter  depends 
largely  upon  its  age  and  origin,  and  it  may  be  hastened  by  tillage.  The 
chemical  analysis  shows  correctly  the  total  organic  carbon,  which  represents, 
as  a rule,  but  little  more  than  half  the  organic  matter;  so  that  20,000 
pounds  of  organic  carbon  in  the  plowed  soil  of  an  acre  correspond  to  nearly 


1913] 


La  Salle  County 


37 


20  tons  of  organic  matter.  But  this  organic  matter  consists  largely  of  the 
old  organic  residues  that  have  accumulated  during  the  past  centuries  because 
they  were  resistant  to  decay,  and  2 tons  of  clover  or  cowpeas  plowed  under 
may  have  greater  power  to  liberate  plant  food  than  the  20  tons  of  old,  inactive 
organic  matter.  The  recent  history  of  the  individual  farm  or  field  must  be 
depended  upon  for  information  concerning  recent  additions  of  active  organic 
matter,  whether  in  applications  of  farm  manure,  in  legume  crops,  or  in  grass- 
root  sods  of  old  pastures. 

Probably  no  agricultural  fact  is  more  generally  known  by  farmers  and 
landowners  than  that  soils  differ  in  productive  power.  Even  tho  plowed 
alike  and  at  the  same  time,  prepared  the  same  way,  planted  the  same  day 
with  the  same  kind  of  seed,  and  cultivated  alike,  watered  by  the  same  rains 
and  warmed  by  the  same  sun,  nevertheless  the  best  acre  may  produce  twice 
as  large  a crop  as  the  poorest  acre  on  the  same  farm,  if  not,  indeed,  in  the 
same  field;  and  the  fact  should  be  repeated  and  emphasized  that  with  the 
normal  rainfall  of  Illinois  the  productive  power  of  the  land  depends  primarily 
upon  the  stock  of  plant  food  contained  in  the  soil  and  upon  the  rate  at  which 
it  -is  liberated,  just  as  the  success  of  the  merchant  depends  primarily  upon 
his  stock  of  goods  and  the  rapidity  of  sales.  In  both  cases  the  stock  of  any 
commodity  must  be  increased  or  renewed  whenever  the  supply  of  such  com- 
modity becomes  so  depleted  as  to  limit  the  success  of  the  business,  whether 
on  the  farm  or  in  the  store. 

As  the  organic  matter  decays,  certain  decomposition  products  are  formed, 
including  much  carbonic  acid,  some  nitric  acid,  and  various  organic  acids, 
and  these  have  power  to  act  upon  the  soil  and  dissolve  the  essential  mineral 
plant  foods,  thus  furnishing  soluble  phosphates,  nitrates,  and  other  salts  of 
potassium,  magnesium,  calcium,  etc.,  for  the  use  of  the  growing  crop. 

' As  already  explained,  fresh  organic  matter  decomposes  much  more  rap- 
idly than  the  old  humus,  which  represents  the  organic  residues  most  resistant 
to  decay  and  which  consequently  has  accumulated  in  the  soil  during  the 
past  centuries.  The  decay  of  this  old  humus  can  be  hastened  both  by  tillage, 
which  maintains  a porous  condition  and  thus  permits  the  oxygen  of  the  air 
to  enter  the  soil  more  freely  and  to  effect  the  more  rapid  oxidation  of  the 
organic  matter,  and  also  by  incorporating  with  the  old,  resistant  residues 
some  fresh  organic  matter,  such  as  farm  manure,  clover  roots,  etc.,  which 
decay  rapidly  and  thus  furnish  or  liberate  organic  matter  and  inorganic  food 
for  bacteria,  the  bacteria,  under  such  favorable  conditions,  appearing  to  have 
power  to  attack  and  decompose  the  old  humus.  It  is  probably  for  this  reason 
that  peat,  a very  inactive  and  inefficient  fertilizer  when  used  by  itself,  becomes 
much  more  effective  when  incorporated  with  fresh  farm  manure;  so  that, 
when  used  together,  two  tons  of  the  mixture  may  be  worth  as  much  as  two 
tons  of  manure,  but  if  applied  separately,  the  peat  has  little  value.  Bacterial 
action  is  also  promoted  by  the  presence  of  limestone. 

The  condition  of  the  organic  matter  of  the  soil  is  indicated  more  or  less 
definitely  by  the  ratio  of  carbon  to  nitrogen.  As  an  average,  the  fresh 
organic  matter  incorporated  with  soils  contains  about  twenty  times  as  much 
carbon  as  nitrogen,  but  the  carbohydrates  ferment  and  decompose  much  more 
rapidly  than  the  nitrogenous  matter;  and  the  old  resistant  organic  residues, 
such  as  are  found  in  normal  subsoils,  commonly  contain  only  five  or  six  times 
as  much  carbon  as  nitrogen.  Soils  of  normal  physical  composition,  such 
as  loam,  clay  loam,  silt  loam,  and  fine  sandy  loam,  when  in  good  productive 


38 


Soil  Report  No.  5 


[July, 


condition,  contain  about  twelve  to  fourteen  times  as  much  carbon  as  nitrogen 
in  the  surface  soil ; while  in  old,  worn  soils  that  are  greatly  in  need  of  fresh, 
active,  organic  manures,  the  ratio  is  narrower,  sometimes  falling  below  ten  of 
carbon  to  one  of  nitrogen.  (Except  in  newly  made  alluvial  soils,  the  ratio 
is  usually  narrower  in  the  subsurface  and  subsoil  than  in  the  surface  stratum.) 

It  should  be  kept  in  mind  that  crops  are  not  made  out  of  nothing.  They 
are  composed  of  ten  different  elements  of  plant  food,  every  one  of  which  is 
absolutely  essential  for  the  growth  and  formation  of  every  agricultural  plant. 
Of  these  ten  elements  of  plant  food,  only  two  (carbon  and  oxygen)  are 
secured  from  the  air  by  all  agricultural  plants,  only  one  (hydrogen)  from 
water,  and  seven  from  the  soil.  Nitrogen,  one  of  these  seven  elements 
secured  from  the  soil  by  all  plants,  may  also  be  secured  from  the  air  by  one 
class  of  plants  (legumes),  in  case  the  amount  liberated  from  the  soil  is  insuf- 
ficient; but  even  these  plants  (which  include  only  the  clovers,  peas,  beans,  and 
vetches,  among  our  common  agricultural  plants)  secure  from  the  soil  alone 
six  elements  (phosphorus,  potassium,  magnesium,  calcium,  iron  and  sulfur), 
and  also  utilize  the  soil  nitrogen  so  far  as  it  becomes  soluble  and  available 
during  their  period  of  growth. 

Plants  are  made  of  plant-food  elements  in  just  the  same  sense  that 
a building  is  made  of  wood  and  iron,  brick,  stone,  and  mortar.  Without 
materials,  nothing  material  can  be  made.  The  normal  temperature,  sunshine, 
rainfall,  and  length  of  season  in  central  Illinois  are  sufficient  to  produce 
50  bushels  of  wheat  per  acre,  100  bushels  of  corn,  100  bushels  of  oats,  and 
4 tons  of  clover  hay;  and,  where  the  land  is  properly  drained  and  properly 
tilled,  such  crops  would  frequently  be  secured  if  the  plant  foods  were  present 
in  sufficient  amounts  and  liberated  at  a sufficiently  rapid  rate  to  meet  the  abso- 
lute needs  of  the  crops. 

Crop  Requirements 

The  accompanying  table  shows  the  requirements  of  such  crops  for  the 
five  most  important  plant-food  elements  which  the  soil  must  furnish.  (Iron 
and  sulfur  are  supplied  normally  in  sufficient  abundance  compared  with  the 
amounts  needed  by  plants,  so  that  they  are  not  known  ever  to  limit  the  yield 
of  general  farm  crops  grown  under  normal  conditions.) 


Table  A. — Plant  Food  in  Wheat,  Corn,  Oats,  and  Clover 


Produce 

Nitro- 

gen, 

pounds 

Phos- 

phorus, 

pounds 

Potas- 

sium, 

pounds 

Magne- 

sium, 

pounds 

Cal- 

cium, 

pounds 

Kind 

Amount 

Wheat,  grain 

SO  bu. 

71 

12 

13 

4 

1 

Wheat  straw 

2 yz  tons 

25 

4 

45 

4 

10 

Corn,  grain 

100  bu. 

100 

17 

19 

7 

1 

Corn  stover 

3 tons 

48 

6 

52 

10 

21 

Corn  cobs  

ton 

2 

2 

Oats,  grain 

100  bu. 

66 

11 

16 

4 

2 

Oat  straw 

2 y tons 

31 

5 

52 

7 

15 

Clover  seed 

4 bu. 

7 

2 

3 

1 

1 

Clover  hay 

4 tons 

160 

20 

120 

31 

117 

Total  in  grain  and  Seed 

244 1 

42 

51 

16 

4 

Total  in  four  crops 

5101 

77 

322 

68 

168 

^hese  amounts  include  the  nitrogen  contained  in  the  clover  seed  or  hay,  which, 
however,  may  be  secured  from  the  air. 


La  Salle  County 


39 


1913] 


To  be  sure,  these  are  large  yields,  but  shall  we  try  to  make  possible  the 
production  of  yields  only  half  or  a quarter  as  large  as  these,  or  shall  we 
set  as  our  ideal  this  higher  mark,  and  then  approach  it  as  nearly  as  possible 
with  profit?  Among  the  four  crops,  corn  is  the  largest,  with  a total  yield 
of  more  than  six  tons  per  acre;  and  yet  the  100-bushel  crop  of  corn  is  often 
produced  on  rich  pieces  of  land  in  good  seasons.  In  very  practical  and 
profitable  systems  of  farming,  the  Illinois  Experiment  Station  has  produced, 
as  an  average  of  the  six  years  1905  to  1910,  a yield  of  87  bushels  of  corn 
per  acre  in  grain  farming  (with  limestone  and  phosphorus  applied,  and  with 
crop  residues  and  legume  crops  turned  under),  and  90  bushels  per  acre  in 
live-stock  farming  (with  limestone,  phosphorus,  and  manure). 

The  importance  of  maintaining  a rich  surface  soil  cannot  be  too  strongly 
emphasized.  This  is  well  illustrated  by  data  from  the  Rothamsted  Experi- 
ment Station,  the  oldest  in  the  world.  Thus  on  Broadbalk  field,  where  wheat 
has  been  grown  since  1844,  the  average  yields  for  the  ten  years  1892  to  1901 
were  12.3  bushels  per  acre  on  Plot  3 (unfertilized)  and  31.8  bushels  on 
Plot  7 (well  fertilized),  but  the  amounts  of  both  nitrogen  and  phosphorus 
in  the  subsoil  (9  to  27  inches)  were  distinctly  greater  in  Plot  3 than  in 
Plot  7,  thus  Showing  that  the  higher  yields  from  Plot  7 were  due  to  the 
fact  that  the  plowed  soil  had  been  enriched.  In  1893  Plot  7 contained  per 
acre  in  the  surface  soil  (o  to  9 inches)  about  600  pounds  more  nitrogen  and 
900  pounds  more  phosphorus  than  Plot  3.  Even  a rich  subsoil  has  little 
value  if  it  lies  beneath  a worn-out  surface. 


Methods  oe  Liberating  Plant  Food 

Limestone  and  decaying  organic  matter  are  the  principal  materials  the 
farmer  can  utilize  most  profitably  to  bring  about  the  liberation  of  plant  food. 

The  limestone  corrects  the  acidity  of  the  soil  and  thus  encourages  the 
development  not  only  of  the  nitrogen-gathering  bacteria  which  live  in  the 
nodules  on  the  roots  of  clover,  cowpeas,  and  other  legumes,  but  also  the 
nitrifying  bacteria,  which  have  power  to  transform  the  insoluble  and  unavail- 
able organic  nitrogen  into  soluble  and  available  nitrate  nitrogen. 

At  the  same  time,  the  products  of  this  decomposition  have  power  to  dis- 
solve the  minerals  contained  in  the  soil,  such  as  potassium  and  magnesium, 
and  also  to  dissolve  the  insoluble  phosphate  and  limestone  which  may  be 
applied  in  low-priced  forms. 

Tillage,  or  cultivation,  also  hastens  the  liberation  of  plant  food  by  permit- 
ting the  air  to  enter  the  soil  and  burn  out  the  organic  matter ; but  it  should 
never  be  forgotten  that  tillage  is  wholly  destructive,  that  it  adds  nothing 
whatever  to  the  soil,  but  always  leaves  the  soil  poorer.  Tillage  should  be 
practiced  so  far  as  is  necessary  to  prepare  a suitable  seed-bed  for  root  devel- 
opment and  also  for  the  purpose  of  killing  weeds,  but  more  than  this  is 
unnecessary  and  unprofitable  in  seasons  of  normal  rainfall;  and  it  is  much 
better  actually  to  enrich  the  soil  by  proper  applications  or  additions,  including 
limestone  and  organic  matter  (both  of  which  have  power  to  improve  the 
physical  condition  as  well  as  to  liberate  plant  food)  than  merely  to  hasten 
soil  depletion  by  means  of  excessive  cultivation. 

Permanent  Soil  Improvement 

The  best  and  most  profitable  methods  for  the  permanent  improvement  of 
the  common  soils  of  Illinois  are  as  follows : 


40 


Soil  Report  No.  5 


t July, 


(1)  If  the  soil  is  acid,  apply  at  least  two  tons  per  acre  of  ground  lime- 
stone, preferably  at  times  magnesian  limestone  (CaC03MgC03),  which 
contains  both  calcium  and  magnesium  and  has  slightly  greater  power  to  cor- 
rect soil  acidity,  ton  for  ton,  than  the  ordinary  calcium  limestone  (CaC03)  ; 
and  continue  to  apply  about  two  tons  per  acre  of  ground  limestone  every  four 
or  five  years.  On  strongly  acid  soils,  or  in  preparing  the  land  for  alfalfa,  five 
tons  per  acre  of  ground  limestone  may  well  be  used  for  the  first  application. 

(2)  Adopt  a good  rotation  of  crops,  including  a liberal  use  of  legumes, 
and  increase  the  organic  matter  of  the  soil  either  by  plowing  under  the 
legume  crops  and  other  crop  residues  (straw  and  corn  stalks),  or  by  using 
for  feed  and  bedding  practically  all  the  crops  raised  and  returning  the 
manure  to  the  land  with-  the  least  possible  loss.  No  one  can  say  in  advance 
what  will  prove  to  be  the  best  rotation  of  crops,  because  of  variation  in 
farms  and  farmers,  and  in  prices  for  produce,  but  the  following  are  suggested 
to  serve  as  models  or  outlines : 

First  year,  corn. 

Second  year,  corn. 

Third  year,  wheat  or  oats  (with  clover  or  clover  and  grass). 

Fourth  year,  clover  or  clover  and  grass. 

Fifth  year,  wheat  and  clover  or  grass  and  clover. 

Sixth  year,  clover  or  clover  and  grass. 

Of  course  there  should  be  as  many  fields  as  there  are  years  in  the  rota- 
tion. In  grain  farming,  with  small  grain  grown  the  third  and  fifth  years,  most 
of  the  coarse  products  should  be  returned  to  the  soil,  and  the  clover  may  be 
clipped  and  left  on  the  land  (only  the  clover  seed  being  sold  the  fourth  and 
sixth  years)  ; or,  in  live-stock  farming,  the  field  may  be  used  three  years  for 
timothy  and  clover  pasture  and  meadow  if  desired.  The  system  may  be 
reduced  to  a five-year  rotation  by  cutting  out  either  the  second  or  the  sixth 
year,  and  to  a four-year  system  by  omitting  the  fifth  and  sixth  years. 

With  two  years  of  corn,  followed  by  oats  with  clover-seeding  the  third 
year,  and  by  clover  the  fourth  year,  all  produce  can  be  used  for  feed  and 
bedding  if  other  land  is  available  for  permanent  pasture.  Alfalfa  may  be 
grown  on  a fifth  field  for  four  or  eight  years,  which  is  to  be  alternated  with 
one  of  the  four;  or  the  alfalfa  may  be  moved  every  five  years,  and  thus 
rotated  over  all  five  fields  every  twenty-five  years. 

Other  four-year  rotations  more  suitable  for  grain  farming  are ; 

Wheat  (and  clover),  corn,  oats,  and  clover;  or  corn  (and  clover),  cowpeas,  wheat, 
and  clover.  (Alfalfa  may  be  grown  on  a fifth  field  and  rotated  every  five  years, 
the  hay  being  sold.) 

Good  three-year  rotations  are; 

Corn,  oats,  and  clover;  corn,  wheat,  and  clover;  or  wheat  (and  clover),  corn  (and 
clover),  and  cowpeas,  in  which  two  cover  crops  and  one  regular  crop  of  legumes 
are  grown  in  three  years. 

A five-year  rotation  of  (1)  corn  (and  clover),  (2)  cowpeas,  (3)  wheat, 
(4)  clover,  and  (5)  wheat  (and  clover)  allows  legumes  to  be  seeded  four 
times,  and  alfalfa  may  be  grown  on  a sixth  field  for  five  or  six  years  in  the 
combination  rotation,  alternating  between  two  fields  every  five  years,  or 
rotating  over  all  the  fields  if  moved  every  six  years. 

To  avoid  clover  sickness  it  may  sometimes  be  necessary  to  substitute  sweet 
clover  or  alsike  for  red  clover  in  alxnit  every  third  rotation,  and  at  the  same 


La  Salle  County 


41 


1913] 

time  to  discontinue  its  use  in  the  cover-crop  mixture.  If  the  corn  crop 
is  not  too  rank,  cowpeas  or  soybeans  may  also  be  used  as  a cover  crop  (seeded 
at  the  last  cultivation)  in  the  southern  part  of  the  state,  and,  if  necessary 
to  avoid  disease,  these  may  well  alternate  in  successive  rotations. 

For  easy  figuring  it  may  well  be  kept  in  mind  that  the  following  amounts 
of  nitrogen  are  required  for  the  produce  named : 

1 bushel  of  oats  (grain  and  straw)  requires  1 pound  of  nitrogen. 

1 bushel  of  corn  (grain  and  stalks)  requires  pounds  of  nitrogen. 

1 bushel  of  wheat  (grain  and  straw)  requires  2 pounds  of  nitrogen. 

1 ton  of  timothy  requires  24  pounds  of  nitrogen. 

1 ton  of  clover  contains  40  pounds  of  nitrogen. 

I ton  of  cowpeas  contains  43  pounds  of  nitrogen. 

I ton  of  average  manure  contains  10  pounds  of  nitrogen. 

The  roots  of  clover  contain  about  half  as  much  nitrogen  as  the  tops,  and 
the  roots  of  cowpeas  contain  about  one-tenth  as  much  as  the  tops. 

Soils  of  moderate  productive  power  will  furnish  as  much  nitrogen  to 
clover  (and  two  or  three  times  as  much  to  cowpeas)  as  will  be  left  in  the 
roots  and  stubble.  For  grain  crops,  such  as  wheat,  corn,  and  oats,  about  two- 
thirds  of  the  nitrogen  is  contained  in  the  grain  and  one-third  in  the  straw 
or  stalks.  (See  also  discussion  of  “The  Potassium  Problem,”  on  pages  below.) 

(3)  On  all  lands  deficient  in  phosphorus  (except  on  those  susceptible 
to  serious  erosion  by  surface  washing  or  gullying)  apply  that  element  in 
considerably  larger  amounts  than  are  required  to  meet  the  actual  needs  of 
the  crops  desired  to  be  produced.  The  abundant  information  thus  far  se- 
cured shows  positively  that  fine-ground  natural  rock  phosphate  can  be  used 
successfully  and  very  profitably,  and  clearly  indicates  that  this  material  will 
be  the  most  economical  form  of  phosphorus  to  use  in  all  ordinary  systems 
of  permanent,  profitable  soil  improvement.  The  first  application  may  well 
be  one  ton  per  acre,  and  subsequently  about  one-half  ton  per  acre  every  four 
or  five  years  should  be  applied,  at  least  until  the  phosphorus  content  of  the 
plowed  soil  reaches  2,000  pounds  per  acre,  which  may  require  a total  ap- 
plication of  from  three  to  five  or  six  tons  per  acre  of  raw  phosphate  con- 
taining 12*4  percent  of  the  element  phosphorus. 

Steamed  bone  meal  and  even  acid  phosphate  may  be  used  in  emergencies, 
but  it  should  always  be  kept  in  mind  that  phosphorus  delivered  in  Illinois 
costs  about  3 cents  a pound  in  raw  phosphate  (direct  from  the  mine  in  car- 
load lots),  but  10  cents  a pound  in  steamed  bone  meal,  and  about  12  cents 
a pound  in  acid  phosphate,  both  of  which  cost  too  much  per  ton  to  permit 
their  common  purchase  by  farmers  in  carload  lots,  which  is  not  the  case 
with  limestone  or  raw  phosphate. 

Phosphorus  once  applied  to  the  soil  remains  in  it  until  removed  in  crops, 
unless  carried  away  mechanically  by  soil  erosion.  (The  loss  by  leaching 
is  only  about  il/2  pounds  per  acre  per  annum,  so  that  more  than  150  years 
would  be  required  to  leach  away  the  phosphorus  applied  in  one  ton  of  raw 
phosphate.) 

The  phosphate  and  limestone  may  be  applied  at  any  time  during  the 
rotation,,  but  a good  method  is  to  apply  the  limestone  after  plowing  and 
work  it  into  the  surface  soil  in  preparing  the  seed  bed  for  wheat,  oats,  rye, 
or  barley,  where  clover  is  to  be  seeded;  while  phosphate  is  best  plowed  under 
with  farm  manure,  clover,  or  other  green  manures,  which  serve  to  liberate 
the  phosphorus. 


42 


Soil  Report  No.  5 


[July, 


(4)  Until  the  supply  of  decaying  organic  matter  has  been  made  ade- 
quate, on  the  poorer  types  of  upland  timber  and  gray  prairie  soils  some 
temporary  benefit  may  be  derived  from  the  use  of  a soluble  salt  or  mixture 
of  salts,  such  as  kainit,  which  contains  both  potassium  and  magnesium  in 
soluble  form  and  also  some  common  salt  (sodium  chlorid) . About  600 
pounds  per  acre  of  kainit  applied  and  turned  under  with  the  raw  phosphate 
will  help  to  dissolve  the  phosphorus  as  well  as  to  furnish  available  potas- 
sium and  magnesium,  and  for  a few  yc£rs  such  use  of  kainit  will  no  doubt 
be  profitable  on  lands  deficient  in  organic  matter,  but  the  evidence  thus  far 
secured  indicates  that  its  use  is  not  absolutely  necessary  and  that  it  will  not 
be  profitable  after  adequate  provision  is  made  for  decaying  organic  matter, 
since  this  will  necessitate  returning  to  the  soil  either  all  produce  except  the 
grain  (in  grain  farming)  or  the  manure  produced  in  live-stock  farming. 
(Where  hay  or  straw  is  sold,  manure  should  be  bought.) 

On  soils  which  are  subject  to  surface  washing,  including  especially  the. 
yellow  silt  loam  of  the  upland  timber  area,  and  to  some  extent  the  yellow- 
gray  silt  loam,  and  other  more  rolling  areas,  the  supply  of  minerals  in  the 
subsurface  and  subsoil  (which  gradually  renew  the  surface  soil)  tends  to 
provide  for  a low-grade  system  of  permanent  agriculture  if  some  use  is  made 
of  legume  plants,  as  in  long  rotations  with  much  pasture,  because  both  the 
minerals  and  nitrogen  are  thus  provided  in  some  amount  almost  permanently ; 
but  where  such  lands  are  farmed  under  such  a system,  not  more  than  two  or 
three  grain  crops  should  be  grown  during  a period  of  ten  or  twelve  years, 
the  land  being  kept  in  pasture  most  of  the  time ; and  where  the  soil  is  acid  a 
liberal  use  of  limestone,  as  top-dressings  if  necessary,  and  occasional  re- 
seeding with  clovers  will  benefit  both  the  pasture  and  indirectly  the  grain 
crops. 

Advantage  oe  Crop  Rotation  and  Permanent  Systems 

It  should  be  noted  that  clover  is  not  likely  to  be  well  infected  with  the 
clover  bacteria  during  the  first  rotation  on  a given  farm  or  field  where  it 
has  not  been  grown  before  within  recent  years;  but  even  a partial  stand  of 
clover  the  first  time  will  probably  provide  a thousand  times  as  many  bac- 
teria for  the  next  clover  crop  as  one  could  afford  to  apply  in  artificial  inocu- 
lation, for  a single  root-tubercle  may  contain  a million  bacteria  developed 
from  one  during  the  season’s  growth. 

This  is  only  one  of  several  advantages  of  the  second  course  of  the  rota- 
tion over  the  first  course.  Thus  the  mere  practice  of  crop  rotation  is  an  ad- 
vantage, especially  in  helping  to  rid  the  land  of  insects  and  foul  grass  and 
weeds.  The  deep-rooting  clover  crop  is  an  advantage  to  subsequent  crops 
because  of  that  characteristic.  The  larger  applications  of  organic  manures 
(made  possible  by  the  larger  crops)  are  a great  advantage;  and  in  systems 
of  permanent  soil  improvement,  such  as  are  here  advised  and  illustrated, 
more  limestone  and  more  phosphorus  are  provided  than  are  needed  for  the 
meager  or  moderate  crops  produced  during  the  first  rotation,  and  conse- 
quently the  crops  in  the  second  rotation  have  the  advantage  of  such  accumu- 
lated residues  (well  incorporated  with  the  plowed  soil)  in  addition  to  the 
regular  applications  made  during  the  second  rotation. 

This  means  that  these  systems  tend  positively  toward  the  making  of 
richer  lands.  The  ultimate  analyses  recorded  in  the  tables  give  the  absolute 
invoice  of  these  Illinois  soils.  They  show  that  most  of  them  are  positively 
deficient  only  in  limestone,  phosphorus,  and  nitrogenous  organic  matter:  and 


La  Salle  County 


43 


jpjy] 


the  accumulated  information  from  careful  and  long-continued  investigations 
in  different  parts  of  the  United  States  clearly  establishes  the  fact  that  in  gen- 
eral farming  these  essentials  can  be  supplied  with  greatest  economy  and 
profit  by  the  use  of  ground  natural  limestone,  very  finely  ground  natural 
rock  phosphate,  and  legume  crops  to  be  plowed  under  directly  or  in  farm 
manure.  On  normal  soils  no  other  applications  are  absolutely  necessary, 
but,  as  already  explained,  the  addition  of  some  soluble  salt  in  the  beginning 
of  a system  of  improvement  on  some  of  these  soils  produces  temporary 
benefit,  and  if  some  inexpensive  salt,  such  as  kainit,  is  used,  it  may  produce 
sufficient  increase  to  more  than  pay  the  added  cost. 


Thu  Potassium  Problem 

As  reported  in  Illinois  Bulletin  123,  where  wheat  has  been  grown  every 
year  for  more  than  half  a century  at  Rothamsted,  England,  exactly  the  same 
increase  was  produced  (5.6  bushels  per  acre),  as  an  average  of  the  first 
24  years,  whether  potassium,  magnesium,  or  sodium  was  applied,  the  rate  of 
application  per  annum  being  200  pounds  of  potassium  sulfate  and  molecular 
equivalents  of  magnesium  sulfate  and  sodium  sulfate.  As  an  average  of 
60  years  (1852  to  1911),  the  yield  of  wheat  has  been  12.7  bushels  on  un- 
treated land,  23.3  bushels  where  86  pounds  of  nitrogen  and  29  pounds  of 
phosphorus  per  acre  per  annum  were  applied;  and,  as  further  additions,  85 
pounds  of  potassium  raised  the  yield  to  31.3  bushels;  52  pounds  of  mag- 
nesium raised  it  to  29.2  bushels;  and  50  pounds  of  sodium  raised  it  to 
29.5  bushels.  Where  potassium  was  applied,  the  average  wheat  crop  re- 
moved 40  pounds  of  that  element  in  the  grain  and  straw,  or  three  times  as 
much  as  would  be  removed  in  the  grain  only  for  such  crops  as  are  suggested 
in  Table  A.  The  Rothamsted  soil  contained  an  abundance  of  limestone,  but  no 
organic  matter  was  provided  except  the  little  in  the  stubble  and  roots  of  the 
wheat  plants. 

On  another  field  at  Rothamsted  the  average  yield  of  barley  for  60  years 
(1852  to  1911)  has  been  14.2  bushels  on  untreated  land,  38.1  bushels  where 
43  pounds  of  nitrogen  and  29  pounds  of  phosphorus  have  been  applied 
per  acre  per  annum;  while  the  further  addition  of  85  pounds  of  potassium, 
19  pounds  of  magnesium,  and  14  pounds  of  sodium  (all  in  sulfates)  raised 
the  average  yield  to  41.5  bushels,  but,  where  only  70  pounds  of  sodium  were 
applied  in  addition  to  the  nitrogen  and  phosphorus,  the  average  has  been 
43.0  bushels.  Thus,  as  an  average  of  60  years,  the  use  of  sodium  pro- 
duced 1.8  bushels  less  wheat  and  1.5  bushels  more  barley  than  the  use  of 
potassium,  with  both  grain  and  straw  removed  and  no  organic  manures 
returned. 

In  recent  years  the  effect  of  potassium  is  becoming  much  more  marked 
than  that  of  sodium  or  magnesium,  on  the  wheat  crop;  but  this  must  be 
expected  to  occur  in  time  where  no  potassium  is  returned  in  straw  or  manure, 
and  no  provision  made  for  liberating  potassium  from  the  supply  still  re- 
maining in  the  soil.  If  more  than  three-fourths  of  the  potassium  removed 
were  returned  in  the  straw  (see  Table  A),  and  if  the  decomposition  prod- 
ucts of  the  straw  have  power  to  liberate  additional  amounts  of  potassium 
from  the  soil,  the  necessity  of  purchasing  potassium  in  a good  system  of 
farming  on  such  land  is  very  remote. 

While  about  half  the  potassium,  nitrogen,  and  organic  matter,  and 
about  one-fourth  the  phosphorus  contained  in  manure  will  be  lost  by 
three  or  four  months’  exposure  in  the  ordinary  pile  in  the  barn  yard,  there 


44 


Soil  Report  No.  5 


[July, 


is  practically  no  loss  if  plenty  of  absorbent  bedding  is  used  on  cement  floors, 
and  if  the  manure  is  hauled  to  the  field  and  spread  within  a day  or  two 
after  it  is  produced.  Again,  while  the  animals  destroy  two-thirds  of  the 
organic  matter  and  retain  one-fourth  of  the  nitrogen  and  phosphorus  in 
average  live-stock  farming,  they  retain  less  than  one-tenth  of  the  potassium, 
from  the  food  consumed;  so  that  the  actual  loss  of  potassium  in  the  products 
sold  from  the  farm,  either  in  grain  farming  or  in  live-stock  farming,  is 
wholly  negligible  on  land  containing  25,000  pounds  or  more  of  potassium 
in  the  surface  67^  inches. 

The  removal  of  one  inch  of  soil  per  century  by  surface  washing  (which 
is  likely  to  occur  wherever  there  is  satisfactory  surface  drainage  and  frequent 
cultivation)  would  permanently  maintain  the  potassium  in  grain  farming 
by  renewal  from  the  subsoil,  provided  one-third  of  the  potassium  is  removed 
by  cropping  before  the  soil  is  carried  away. 

From  all  of  these  facts  it  will  be  seen  that  the  potassium  problem  is  not 
one  of  addition  but  of  liberation;  and  the  Rothamsted  records  show  that 
for  many  years  other  soluble  salts  have  practically  the  same  power  as  po- 
tassium to  increase  crop  yields  in  the  absence  of  sufficient  decaying  organic 
matter.  Whether  this  action  relates  to  supplying  or  liberating  potassium  for 
its  own  sake,  or  to  the  power  of  the  soluble  salt  to  increase  the  availability 
of  phosphorus  or  other  elements,  is  not  known,  but  where  much  potassium 
is  removed,  as  in  the  entire  crops  at  Rothamsted,  with  no  return  of  organic 
residues,  probably  the  soluble  salt  functions  in  both  ways. 

As  an  average  of  112  separate  tests  conducted  in  1907,  1908,  1909,  and 
1910  on  the  Fairfield  experiment  field,  an  application  of  200  pounds  of 
potassium  sulfate,  containing  85  pounds  of  potassium  and  costing  $5.10,  in- 
creased the  yield  of  corn  by  9.3  bushels  per  acre;  while  600  pounds  of  kainit, 
containing  only  60  pounds  of  potassium  and  costing  $4.00,  gave  an  increase 
of  10.7  bushels.  Thus,  at  40  cents  a bushel  for  com,  the  kainit  has  paid  for 
itself;  but  these  results,  like  those  at  Rothamsted,  were  secured  where  no 
adequate  provision  had  been  made  for  decaying  organic  matter. 

Additional  experiments  at  Fairfield  include  an  equally  complete  test  with 
potassium  sulfate  and  kainit  on  land  to  which  8 tons  per  acre  of  farm 
manure  had  been  applied.  As  an  average  of  112  tests  with  each  material, 
the  200  pounds  of  potassium  sulfate  increased  the  yield  of  corn  by  1.7  bush- 
els, while  the  600  pounds  of  kainit  also  gave  an  increase  of  1.7  bushels. 
Thus,  where  organic  manure  was  supplied,  very  little  effect  was  produced 
by  the  addition  of  either  potassium  sulfate  or  kainit;  in  part  perhaps  because 
the  potassium  removed  in  the  crops  is  mostly  returned  in  the  manure  if 
properly  cared  for,  and  perhaps  in  larger  part  because  the  decaying  organic 
matter  helps  to  liberate  and  hold  in  solution  other  plant-food  elements,  es- 
pecially phosphorus. 

In  laboratory  experiments  at  the  Illinois  Experiment  Station,  it  has  been 
shown  that  potassium  salts  and  most  other  soluble  salts  increase  the  solu- 
bility of  the  phosphorus  in  soil  and  in  rock  phosphate  as  determined  by  chem- 
ical analysis;  also  that  the  addition  of  glucose  with  rock  phosphate  in  pot- 
culture  experiments  increases  the  availability  of  the  phosphorus,  as  measured 
by  plant  growth,  altho  the  glucose  consists  only  of  carbon,  hydrogen,  and 
oxygen,  and  thus  contains  no  plant  food  of  value. 

If  we  remember  that,  as  an  average,  live  stock  destroy  two-thirds  of  the 
organic  matter  of  the  food  consumed,  it  is  easy  to  determine  from  Table  A 


1913] 


La  Salle  County 


45 


that  more  organic  matter  will  be  supplied  in  a proper  grain  system  than 
in  a strictly  live-stock  system ; and  the  evidence  thus  far  secured  from  older 
experiments  at  the  University  and  at  other  places  in  the  state  indicates  that 
if  the  corn  stalks,  straw,  clover,  etc.,  are  incorporated  with  the  soil  as  soon 
as  practicable  after  they  are  produced  (which  can  usually  be  done  in  the 
late  fall  or  early  spring),  there  is  little  or  no  difficulty  in  securing  sufficient 
decomposition  in  our.  humid  climate  to  avoid  serious  interference  with  the 
capillary  movement  of  the  soil  moisture,  a common  danger  from  plowing  un- 
der too  much  coarse  manure  of  any  kind  in  the  late  spring  of  a dry  year. 

If,  however,  the  entire  produce  of  the  land  is  sold  from  the  farm,  as 
in  hay  farming,  or  when  both  grain  and  straw  are  sold,  of  course  the  draft 
on  potassium  will  then  be  so  great  that  in  time  it  must  be  renewed  by  some 
sort  of  application.  As  a rule,  such  farmers  ought  to  secure  manure  from 
town,  since  they  furnish  the  bulk  of  the  material  out  of  which  manure  is 
produced. 

Calcium'  and  Magnesium 

When  measured  by  the  actual  crop  requirements  for  plant  food,  mag- 
nesium and  calcium  are  more  limited  in  some  Illinois  soils  than  potassium. 
But  with  these  elements  we  must  also  consider  the  loss  by  leaching.  As  an 
average  of  go  analyses1  of  Illinois  well-waters  drawn  chiefly  from  glacial 
sands,  gravels,  or  till,  3 million  pounds  of  water  (about  the  average  annual 
drainag-e  per  acre  for  Illinois)  contained  11  pounds  of  potassium,  130  of 
magnesium,  and  330  of  calcium.  These  figures  are  very  significant,  and  it 
may  be  stated  that  if  the  plowed  soil  is  well  supplied  with  the  carbonates  of 
magnesium  and  calcium,  then  a very  considerable  proportion  of  these 
amounts  will  be  leached  from  that  stratum.  Thus  the  loss  of  calcium  from 
the  plowed  soil  of  an  acre  at  Rothamsted,  England,  where  the  soil  contains 
plenty  of  limestone,  has  averaged  more  than  3C0  pounds  a year  as  determined 
by  analyzing  the  soil  in  1865  and  again  in  1905.  And  practically  the  same 
amount  of  calcium  was  found  by  analyzing  the  Rothamsted  drainage  waters. 

Common  limestone,  which  is  calcium  carbonate  (CaC03),  contains,  when 
pure,  40  percent  of  calcium,  so  that  800  pounds  of  limestone  are  equivalent 
to  320  pounds  of  calcium.  Where  10  tons  per  acre  of  ground  limestone  were 
applied  at  Edgewood,  Illinois,  the  average  annual  loss  during  the  next  ten 
years  amounted  to  790  pounds  per  acre.  The  definite  data  from  careful 
investigations  seem  to  be  ample  to  justify  the  conclusion  that  where  lime- 
stone is  needed  at  least  2 tons  per  acre  should  be  applied  every  4 or  5 years. 

It  is  of  interest  to  note  that  thirty  crops  of  clover  of  four  tons  each 
would  require  3,510  pounds  of  calcium,  while  the  most  common  prairie  land 
of  southern  Illinois  contains  only  3,420  pounds  of  total  calcium  in  the 
plowed  soil  of  an  acre.  (See  Soil  Report  No.  t.)  Thus  limestone  has  a 
positive  value  on  some  soils  for  the  plant  food  which  it  supplies,  in  addition 
to  its  value  in  correcting  soil  acidity  and  in  improving  the  physical  condi- 
tion of  the  soil.  Ordinary  limestone  (abundant  in  the  southern  and  western 
parts  of  the  state)  contains  nearly  800  pounds  of  calcium  per  ton;  while  a 
good  grade  of  dolomitic  limestone  (the  more  common  limestone  of  northern 
Illinois)  contains  about  400  pounds  of  calcium  and  300  pounds  of  mag- 
nesium per  ton.  Both  of  these  elements  are  furnished  in  readily  available 
form  in  ground  dolomitic  limestone. 


Reported  by  Doctor  Bartow  and  associates,  of  the  Illinois  State  Water  Survey. 


UNIVERSITY  OF  ILLINOIS 

Agricultural  Experiment  Station 

■ 

SOIL  REPORT  NO.  6 

KNOX  COUNTY  SOILS 


By  CYRIL  G.  HOPKINS,  J.  G.  MOSIER, 
J.  H.  PETTIT,  and  J.  E.  READHIMER 


URBANA,  ILLINOIS,  AUGUST,  1913 


State  Advisory  Committee  on  Soil  Investigations 
Ralph  Allen,  Delavan  A.  N.  Abbott,  Morrison 

F.  I.  Mann,  Gilman  J.  P.  Mason,  Elgin 

C.  V.  Gregory,  538  S.  Clark  St.,  Chicago. 

Agricultural  Experiment  Station  Staee  on  Soil  Investigations 
Eugene  Davenport,  Director 


Cyril  G.  Hopkins,  Chief 

Soil  Analysis 

J.  H.  Pettit,  Chief 
E.  Van  Alstine,  Associate 
J.  P.  Aumer,  Associate 
W.  H.  Sachs,  First  Assistant 
Gertrude  Niederman,  Assistant 
W.  R.  Leighty,  Assistant 
Oran  Keller,  Assistant 
L.  R.  Binding,  Assistant 

Soil  Experiment  Fields — 

J.  E.  Readhimer,  Superintendent 
Wm.  G.  Eckhardt,1  Associate 
O.  S.  Fisher,  Associate 
J.  E.  Whitchurch,  Associate 

E.  E.  Hoskins,  Associate 

F.  C.  Bauer,  First  Assistant 
F.  W.  Garrett,  Assistant 

‘On  leave. 


in  Agronomy  and  Chemistry 
Soil  Survey — 

J.  G.  Mosier,  Chief 
A.  F.  Gustafson^  Associate 
S.  V.  Holt,  Associate 
H.  W.  Stewart,  Associate 
H.  C.  Wheeler,  Associate 
F.  A.  Fisher,  Assistant 
F.  M.  W.  Wascher,  Assistant 
R.  W.  Dickenson,  Assistant 
John  Woodard,  Assistant 


Soil  Biology 

A.  L.  Whiting,  First  Assistant 

Soils  Extension — 

C.  C.  Logan,  Associate 


introductory  note 

About  two-thirds  of  Illinois  lies  in  the  corn  belt,  where  most  of  the 
prairie  lands  are  black  or  dark  brown  in  color.  In  the  southern  third  of 
the  state,  the  prairie  soils  are  largely  of  a gray  color.  This  region  is  better 
known  as  the  wheat  belt,  altho  wheat  is  often  grown  in  the  corn  belt  and 
corn  is  also  a common  crop  in  the  wheat  belt. 

Moultrie  county,  representing  the  corn  belt ; Clay  county,  which  is  fairly 
representative  of  the  wheat  belt;  and  Hardin  county,  which  is  taken  to  rep- 
resent the  unglaciated  area  of  the  extreme  southern  part  of  the  state,  were 
selected  for  the  first  Illinois  Soil  Reports  by  counties.  While  these  three 
county  soil  reports  were  sent  to  the  Station’s  entire  mailing  list  within  the 
state,  Sangamon,  La  Salle,  and  other  subsequent  reports  are  sent  only  to 
the  residents  of  the  county  concerned  and  to  any  one  else  upon  request. 

Each  county  report  is  intended  to  be  as  nearly  complete  in  itself  as  it 
is  practicable  to  make  it,  and,  even  at  the  expense  of  some  repetition,  each 
will  contain  a general  discussion  of  important  fundamental  principles  to  help 
the  farmer  and  landowner  to  understand  the  meaning  of  the  soil  fertility 
invoice  for  the  lancls  in  which  he  is  interested.  In  Soil  Report  No.  1,  “Clay 
County  Soils,”  this  discussion  serves  in  part  as  an  introduction,  while  in  this 
and  other  reports  it  will  be  found  in  the  Appendix,  but  if  necessary  it  should 
be  read  and  studied  in  advance  of  the  report  proper. 


KNOX  COUNTY  SOILS 

By  CYRIL,  G.  HOPKINS,  J.  G.  MOSIER,  J.  H.  PETTIT,  and  J.  E.  READHIMER 


Knox  county  lies  in  the  upper  Illinois  glaciation  and  has  an  area  of 
720.69  square  miles.  The  general  topography  of  the  northern  and  western 
half  is  undulating  or  slightly  rolling,  while  the  southern  and  southeastern 
portion  is  in  part  badly  broken,  especially  along  Spoon  river  and  its  tributa- 
ries. The  upland  prairie  soils  cover  57  percent  of  the  county,  the  undulating 
timber  lands  about  1434  percent,  the  rough  or  rolling  timber  lands  about  1834 
percent,  and  the  bottom  lands  nearly  10  percent. 

The  difference  in  topography  is  due  to  two  causes — glacial  action  and 
stream  erosion.  Like  most  of  the  state,  this  county  was  covered  by  an  ice 
sheet  during  the  glacial  period.  During  that  time  snow  and  ice  accumulated 
in  the  region  of  Hudson  Bay  to  such  an  amount  that  it  pushed  southward 
until  a point  was  reached  where  the  ice  melted  as  rapidly  as  it  advanced.  In 
moving  across  the  country,  the. ice  gathered  up  all  sorts  and  sizes  of  material, 
including  pebbles,  boulders,  and  even  large  masses  of  rock.  Many  of  these 
were  carried  hundreds  of  miles  and  rubbed  against  the  surface  rocks  or  against 
each  other  until  ground  into  powder.  When  the  limit  of  advance  was  reached, 
where  the  ice  largely  melted,  this  material  would  accumulate  in  a broad  un- 
dulating ridge,  or  moraine.  When  the  ice  melted  away  more  rapidly  than  the 
glacier  advanced,  the  terminus  of  the  glacier  would  recede  and  leave  a drift 
of  boulder  clay  deposited  somewhat  uniformly,  yet  not  entirely  so,  over  the 
inter-morainal  tract  marking  the  area  previously  covered  by  the  ice  sheet. 
These  intermorainal  tracts  are  occupied  chiefly  by  level,  undulating,  or  rolling 
plains. 

The  material  transported  by  the  glacier  varied  with  the  character  of  the 
rocks  over  which  it  passed.  Granites,  limestones,  sandstones,  shales,  etc., 
were  mixed  and  ground  up  together.  This  mixture  of  all  kinds  of  material, 
boulders,  gravel,  sand,  silt,  and  clay,  is  called  boulder  clay,  till,  glacial  drift, 
or  simply  drift.  The  grinding  and  denuding  power  of  glaciers  is  enormous. 
A mass  of  ice  100  feet  thick  exerts  a pressure  of  40  pounds  per  square  inch 
and  this  ice  sheet  may  have  been  thousands  of  feet  in  thickness.  The  mate- 
rials carried  along  in  this  mass  of  ice,  especially  the  boulders  and  pebbles,  be- 
came powerful  agents  for  grinding  and  wearing  away  the  surface  over  which 
the  ice  passed.  Preglacial  ridges  and  hills  were  rubbed  down,  valleys  were 
filled  with  the  debris,  and  the  surface  features  changed  entirely. 

The  depth  of  boulder  clay  over  Knox  county  averages  near  30  feet.  No 
continuous  morainal  ridges  occur;  if  they  ever  existed,  they  have  been  torn 
down  thru  erosion  until  now  they  are  represented  by  a few  high  and  some- 
what isolated  areas  whose  locations  are  shown  upon  the  map  by  broken  lines. 
These  are  also  indicated  by  serial  numbers  200  instead  of  500.  (See  Bulletin 
123,  state  map  and  pages  257  and  258.)  There  are  two  of  these  morainal 
areas  in  the  county,  one  northwest  and  north  of  Oneida  and  the  other  south- 


1 


2 Soil  Report  No.  6 l August, 

west  of  Yates  City.  This  latter  was  probably  at  one  time  a continuous  ridge, 
but  it  has  been  cut  in  two  by  Spoon  river  and  Willow  creek. 

Physiography  and  Altitude 

The  northwest  quarter  of  the  county  drains  into  the  Mississippi  river; 
the  rest  drains,  principally  thru  Spoon  river  into  the  Illinois.  The  divide 
between  the  two  rivers  extends  south  and  southwest  from  Section  2,  Town- 
ship 13  North,  Range  2 East  of  the  Fourth  Principal  Meridian,  leaving  the 
county  in  the  northwest  corner  of  Township  10  North,  Range  1 East.  The 
altitude  of  the  divide  varies  from  770  to  840  feet  above  sea  level.  The  aver- 
age altitude  of  the  county  is  725  feet.  The  highest  point,  859  feet,  is  in  Sec- 
tion 10,  Township  13  North,  Range  4 East,  while  the  lowest,  about  536  feet, 
is  where  Spoon  river  leaves  the  county. 

Spoon  river  and  its  tributaries  have  produced  quite  a variation  in  topog- 
raphy. The  valleys  of  these  streams  are  from  50  to  200  feet  or  more  below 
the  general  level  of  the  upland.  This  has  permitted  the  small  streams  enter- 
ing the  river  to  do  a large  amount  of  erosion,  and  as  a result  the  land  adja- 
cent to  the  bottom  land  of  the  larger  streams  is  cut  up  into  hills  and  valleys 
unsuited  for  ordinary  agriculture.  Before  the  land  was  put  under  cultivation, 
forests  had  extended  their  way  up  the  streams  and  were  slowly  invading  the 
adjoining  prairies. 

Soil  Material  and  Soil  Types 

The  Illinois  glacier  covered  Knox  county  and  left  a thick  mantle  of  drift, 
completely  burying  the  old  soil  that  preceded  it.  After  this  a long  period 
elapsed  during  which  a deep  soil,  known  as  the  old  Sangamon  soil,1  was 
formed  on  the  Illinois  drift.  Later,  other  ice  invasions  occurred,  but  they 
covered  only  the  northern  and  northeastern  parts  of  the  state.  (See  state 
map  in  Bulletin  123,  Iowan  and  Wisconsin  glaciations.)  These  ice  sheets 
did  not  reach  Knox  county,  but  finely-ground  rock  (rock  flour)  in  immense 
quantities  was  carried  south  by  the  waters  from  the  melting  ice  and  deposited 
on  the  flooded  plains,  where  it  was  picked  up  by  the  wind,  carried  farther, 
and  finally  deposited  upon  the  surface,  burying  the  drift  material  of  the  Illi- 
nois glaciation  and  the  old  Sangamon  soil  to  a depth  of  5 to  50  feet  or  more. 
This  wind-blown  material,  called  loess,  represents  a mixture  pf  all  kinds  of 
material  over  which  the  glacier  passed.  The  deeper  deposit  is  nearer  and  on 
the  east  side  of  the  larger  stream  courses  and  opposite  the  greatest  width  of 
bottom  land.  Its  average  depth  in  this  county  is  about  15  feet.  Soil  has  been 
formed  from  this  comparatively  new  material. 

The  soils  of  Knox  county  are  divided  into  three  classes,  as  follows: 

(1)  Upland  prairie  soils,  rich  in  organic  matter.  These  were  originally 
covered  with  wild  prairie  grasses,  the  partially  decayed  roots  of  which  have 
been  the  source  of  the  organic  matter.  The  flat  prairie  land  contains  the 
higher  amount  of  this  constituent  because  the  grasses  and  roots  grew  more 
luxuriantly  there  and  the  higher  moisture  content  largely  preserved  them  from 
decay. 

(2)  Upland  timber  soils,  including  those  zones  along  stream  courses  over 
which  forests  once  extended.  These  soils  contain  much  less  organic  matter 

'The  Sangamon  soil  may  sometimes  be  seen  in  cuts  as  a somewhat  dark  or  bluish  sticky 
clay  or  a weathered  zone  of  yellowish  or  brownish  clay. 


•*w^uwo. 


~ Z Aiello  o s.  mhto 


SOIL  SURVEY  M 

UNIVERSITY  OF  ILLINOIS  AG 


UPLAND  PRAIRIE  SOILS 

Brown  silt  loam 


H 

|jy  Black  clay  loam 

Brown-gray  silt  loam  on  tight  i 


Lolorii 


Leton 


SWAMP  AND  BOTTOM 
LAND  SOILS 


J lilt  loam 


s§ 


Deep  brown  silt  loam 


s 


Illinois  Moraines 


j,  am 

1 1 loam  on  tight  clay 


^3oT|  Deep  peat 

|Om]  Shallow  peat  on  clay 


2 Milrs 


OF  KNOX  COUNTY 

jULTURAL  EXPERIMENT  STATION 


PE  OKXA  C OU  NTY 


Knox  County 


3 


1913] 


because  the  large  roots  of  dead  trees  and  the  surface  accumulations  of  leaves, 
twigs,  and  fallen  trees  were  burned  by  forest  fires  or  suffered  almost  complete 
decay.  The  timber  lands  are  divided  chiefly  into  two  classes — the  undulating 
and  the  hilly  areas. 

(3)  Swamp  and  bottom  lands,  which  include  the  flood  plains  along 
streams  and  some  small  peaty  swamp  areas. 

Table  1 gives  the  area  of  each  type  of  soil  in  the  county  and  its  percentage 
of  the  total  area.  It  will  be  observed  that  more  than  half  the  entire  county 
is  covered  with  the  common  prairie  soil  known  as  brown  silt  loam,  and  that 
about  one-third  consists  of  two  upland  timber  types,  the  yellow  silt  loam 
(hilly)  and  the  yellow-gray  silt  loam  (undulating),  the  former  occupying 
almost  one-fifth  of  the  entire  county. 


Table  1. — Son,  Types  of  Knox  County 


Soil  | 
type 
No.  1 

Name  of  type 

Area  in 
square 
miles 

Area 

in 

acres 

Percent 

of 

total  area 

526 

(a)  Upland  Prairie  Soils  (page  22) 

Brown  silt  loajn 

402.60 

257  664 

55.87 

520 

Black  clay  loam 

8.31 

5 318 

1.15 

528 

Brown-gray  silt  loam  on  tight  clay 

.46 

295 

.06 

534 

(b)  Upland  Timber  Soils  (page  26) 

Yellow-gray  silt  loam 

104.43 

66  836 

14.48 

535 

Yellow  silt  loam  

133.71 

85  574 

18.56 

532 

Light  gray  silt  loam  on  tight  clay 

.02 

12 

.003 

1326 

(c)  Swamp  and  Bottom-Land  Soils  (page  30) 
Deep  brown  silt  loam 

71.09 

45  498 

9.86 

1303 

Shallow  peat  on  clay 

.03 

19 

.004 

1301 

Deep  peat. 

.04 

26 

.006 

Total 

720.69 

461  242 

100.00 

1Soil  types  Nos.  226,  234,  235,  and  232,  as  found  on  the  maps,  represent  the  same 
types  as  Nos.  ,526,  534,  535,  and  532,  except  that  the  former  are  found  on  morainal  areas. 


The  accompanying  maps  show  the  location  and  boundary  lines  of  every 
type  of  soil  in  the  county,  even  down  to  areas  of  a few  acres;  and  in  Table 
2 are  reported  the  amounts  of  organic  carbon  (the  best  measure  of  the  or- 
ganic matter)  and  the  total  amounts  of  the  five  important  elements  of  plant 
food  contained  in  2 million  pounds  of  the  surface  soil  of  each  type  (the 
plowed  soil  of  an  acre  about  6^  inches  deep).  In  addition,  the  table  shows 
the  amount  of  limestone  present,  if  any,  or  the  amount  of  limestone  required 
to  neutralize  the  acidity  existing  in  the  soil.1 

’The  figures  given  in  Table  2 (and  in  the  corresponding  tables  for  subsurface  and  sub- 
soil) are  the  averages  for  all  determinations  with  some  exceptions  of  limestone  present  or 
required.  Some  soil  types, _ particularly  those  which  are  subject  to  erosion,  may  vary  from 
acid  to  alkaline,  especially  in  the  subsurface  or  subsoil ; and  in  such  cases  the  word  used  in 
the  table  (see  Table  11)  is  more  useful  than  any  average  of  figures  involving  both  plus 
and  minus  quantities. 


Soil  Report  No.  6 


[August, 


THE  INVOICE  AND  INCREASE  OF  FERTILITY  IN  KNOX 
COUNTY  SOILS 

Soil  Analysis 

In  order  to  avoid  confusion  in  applying  in  a practical  way  the  technical 
information  contained  in  this  report,  the  results  are  given  in  the  most  simpli- 
fied form.  The  composition  reported  for  a given  soil  type  is,  as  a rule,  the 
average  of  many  analyses,  which,  like  most  things  in  nature,  show  more  or 
less  variation ; but  for  all  practical  purposes  the  average  is  most  trustworthy 
and  sufficient.  (See  Bulletin  123,  which  reports  the  general  soil  survey  of 
the  state,  together  with  many  hundred  individual  analyses  of  soil  samples 
representing  twenty-five  of  the  most  important  and  most  extensive  soil  types 
in  the  state.) 

The  chemical  analysis  of  the  soil  gives  the  invoice  of  fertility  actually 
present  in  the  soil  strata  sampled  and  analyzed,  but,  as  explained  in  the  Ap- 
pendix, the  rate  of  liberation  is  governed  by  many  factors.  Also,  as  there 
stated,  probably  no  agricultural  fact  is  more  generally  known  by  farmers  and 
landowners  than  that  soils  differ  in  productive  power.  Even  tho  plowed  alike 
and  at  the  same  time,  prepared  the  same  way,  planted  the  same  day  with 
the  same  kind  of  seed,  and  cultivated  alike,  watered  by  the  same  rains  and 
warmed  by  the  same  sun,  nevertheless  the  best  acre  may  produce  twice  as 
large  a crop  as  the  poorest  acre  on  the  same  farm,  if  not,  indeed,  in  the  same 
field;  and  the  fact  should  be  repeated  and  emphasized  that  the  productive 
power  of  normal  soil  in  humid  sections  depends  upon  the  stock  of  plant  food 
contained  in  the  soil  and  upon  the  rate  at  which  it  is  liberated. 

The  fact  may  be  repeated,  too,  that  crops  are  not  made  out  of  nothing. 
They  are  composed  of  ten  different  elements  of  plant  food,  every  one  of 
which  is  absolutely  essential  for  the  growth  and  formation  of  every  agri- 
cultural plant.  Of  these  ten  elements  of  plant  food,  only  two  (carbon  and 
oxygen)  are  secured  from  the  air  by  all  plants,  only  one  (hydrogen)  from 
water,  while  seven  are  secured  from  the  soil.  Nitrogen,  one  of  these 
seven  elements  secured  from  the  soil  by  all  plants,  may  also  be  secured  from 
the  air  by  one  class  of  plants  (legumes)  in  case  the  amount  liberated  from 
the  soil  is  insufficient.  But  even  the  leguminous  plants  (which  include  the 
clovers,  peas,  beans,  alfalfa,  and  vetches),  in  common  with  other  agricultural 
plants,  secure  from  the  soil  alone  six  elements  (phosphorus,  potassium,  mag- 
nesium, calcium,  iron,  and  sulfur)  and  also  utilize  the  soil  nitrogen  so  far 
as  it  becomes  soluble  and  available  during  their  period  of  growth. 

Table  A in  the  Appendix  shows  the  requirements  of  large  crops  for  the 
five  most  important  plant-food  elements  which  the  soil  must  furnish.  (Iron 
and  sulfur  are  supplied  normally  from  natural  sources  in  sufficient  abundance 
compared  with  the  amounts  needed  by  piants,  so  that  they  are  never  known 
to  limit  the  yield  of  common  farm  crops.) 

As  stated,  the  data  in  Table  2 represent  the  total  amounts  of  plant-food 
elements  found  in  2 million  pounds  of  surface  soil,1  which  corresponds  to  an 
acre  about  6^3  inches  deep.  This  includes  at  least  as  much  soil  as  is  ordi- 
narily turned  with  the  plow,  and  represents  that  part  with  which  the  farm 
manure,  limestone,  phosphate,  or  other  fertilizer  applied  in  soil  improve- 
ment is  incorporated.  It  is  the  soil  stratum  that  must  be  depended  upon 


JThe  weight  of  peat  is  figured  at  V2  the  weight  of  normal  soils. 


WARREN  COUNJTYS  z5rH 


GALESBURG 


LEGEND 


UPLAND  PRAIRIE  SOILS  UPLAND  TIMBER  S(| 


Brown  silt  loam 


IH  Ye"f 


jj|j  Black  clay  loam  [|§|  Yollcjl 

[s|||  Brown -gray  eilt  loam  on  tight  clay  [532  | LiglW' 


SOIL  SURVEY  MS 

UNIVERSITY  OF  ILLINOIS  AGL 


OF  KNOX  COUNTY 

EXPERIMENT  STATION 


0 


Illinois  Moraines 


silt  loam  on  tight  clay 


|l326j  Deep  brown  silt  loam 

j I30l|  Deep  peat 

|t3oi|  Shallow  peat  on  clay 


t 


PEORIA  COUNTY 


Knox  County 


S 


1913) 


Table  2. — Fertility  in  the  Soils  of  Knox  County 
Average  pounds  per  acre  in  2 million  pounds  of  surface  soil1  (about  0 to  6%  inches) 


Soil 

type 

No. 

Soil  type 

Total 

organic 

carbon 

Total 

nitro- 

gen 

Total 

phos- 

phorus 

Prairia  5 

Total 

potas- 

sium 

nils 

Total 

magne- 

sium 

Total 

calcium 

Lime- 

stone 

present 

Lime- 

stone 

requir’d 

526 

Brown  silt  loam 

65  750 

5 150 

1 200 

32  730 

9 670 

12  400 

70 

520 

Black  clay  loam 

92  450 

7 650 

1 840 

29  710 

13  830 

23  880 

40 

528 

Brown-gray  silt 
loam  on  tight 
clay 

43  960 

3 320 

1 000 

33  900 

7 900 

9 560 

80 

Upland  Timber  Soils 


534 

Yellow-gray  silt 
loam 

25  900 

2 440 

860 

33  930 

6 620 

8 300 

120 

535 

532 

Y ellow  silt  loam 
Light  gray  silt 
loam  on  tight 

25  420 

2 330 

820 

36  100 

7 090 

7 930 

60 

clay 

26  480 

2 020 

980 

36  020 

6 500 

9 160 

80 

Swamp  and  Bottom  Land  Soils 


Deep  brown  silt 

loam 

60  790 

4 910 

1 790 

36  190 

10  250 

12  130 

Deep  peat 

222  100 

15  730 

1 410 

3 660 

8 590 

160  960 

345  670 

Shallow  peat  on 

clay 

279  660 

21  870 

2 070 

8 920 

8 660 

26  760 

4 810 

‘In  1 million  pounds  of  peat  (1301  and  1303). 


in  large  part  to  furnish  the  necessary  plant  food  for  the  production  of 
crops,  as  will  be  seen  from  the  information  given  in  the  Appendix.  Even 
a rich  subsoil  has  little  or  no  value  if  it  lies  beneath  a worn-out  surface,  but 
if  the  fertility  of  the  surface  soil  is  maintained  at  a high  point,  then  the  strong, 
vigorous  plants  will  have  power  to  secure  more  plant  food  from  the  sub- 
surface and  subsoil  than  would  weak,  shallow-rooted  plants. 

By  easy  computation  it  will  be  found  that  the  most  common  prairie  soil 
of  Knox  county  does  not  contain  more  than  enough  total  nitrogen  in  the 
plowed  soil  for  the  production  of  maximum  crops  for  ten  rotations  (40 
years)  ; while  the  upland  timber  soils  contain,  as  an  average,  less  than  one- 
half  as  much  nitrogen  as  the  prairie  land. 

With  respect  to  phosphorus,  the  condition  differs  only  in  degree,  nine- 
tenths  of  the  soil  area  of  the  county  containing  no  more  of  that  element 
than  would  be  required  for  sixteen  crop  rotations  if  such  yields  were  se- 
cured as  are  suggested’in  Table  A of  the  Appendix.  It  will  be  seen  from 
the  same  table  that  in  the  case  of  the  cereals  about  three-fourths  of  the 
phosphorus  taken  from  the  soil  is  deposited  in  the  grain,  while  only  one- 
fourth  remains  in  the  straw  or  stalks. 

On  the  other  hand,  the  potassium  is  sufficient  for  25  centuries  if  only  the 
grain  is  sold,  or  for  400  years  even  if  the  total  crops  should  be  removed  and 
nothing  returned.  The  corresponding  figures  are  about  2500  and  600  years 
for  magnesium,  and  about  15,000  and  300  years  for  calcium. 

Thus,  when  measured  by  the  actual  crop  requirements  for  plant  food, 
potassium  is  no  more  limited  than  magnesium  and  calcium,  and,  as  explained 
in  the  Appendix,  with  these  elements  we  must  also  consider  the  fact  that  loss 
by  leaching  is  far  greater  than  by  cropping. 


Soil  Report  No.  6 


[August, 


These  general  statements  relating  to  the  total  quantities  of  plant  food 
in  the  plowed  soil  certainly  emphasize  the  fact  that  the  supplies  of  some  of 
these  necessary  elements  of  fertility  are  extremely  limited  when  measured 
by  the  needs  of  large  crop  yields  for  even  one  or  two  generations  of  people. 

The  variation  among  the  different  soil  types  with  respect  to  their  content 
of  important  plant-food  elements  is  also  very  marked.  Thus,  the  prairie 
soils  contain  two  to  three  times  as  much  nitrogen  as  the  timber  lands 
of  the  same  topography ; and  the  richest  prairie  land  contains  twice  as  much 
phosphorus  as  the  common  upland  timber  soils. 

On  the  other  hand,  the  most  significant  fact  revealed  by  the  investiga- 
tion of  the  Knox  county  soils  is  the  low  phosphorus  content  of  the  com- 
mon brown  silt  loam  prairie,  a type  of  soil  which  covers  more  than  half  the 
entire  county.  The  market  value  of  this  land  is  about  $200  an  acre,  and  yet 
an  application  of  forty  dollars’  worth  of  fine-ground  raw  rock  phosphate 


Plate;  1.  Wheat  in  1911  on  Urbana  Field 
Cover  Crops  and  Crop  Residues  Plowed  Under 
Average  Yield,  3S.2  Bushels  Per  Acre 


Knox  County 


7 


would  double  the  phosphorus  content  of  the  plowed  soil,  and,  if  properly 
made,  would  in  the  near  future  double  the  yield  of  clover  on  the  normal 
prairie  soil  and  the  undulating  upland  timber  soils.  If  the  clover  was  then 
returned  to  the  soil,  either  directly  or  in  farm  manure,  the  combined  effect  of 
phosphorus  and  increased  nitrogenous  organic  matter,  with  a good  rotation 
of  crops,  would  in  time  double  the  yield  of  corn  on  most  farms. 

With  5,000  pounds  of  nitrogen  in  the  prairie  soil  and  an  inexhaustible 
supply  in  the  air,  with  33,000  pounds  of  potassium  in  the  same  soil  and  with 
practically  no  acidity,  the  economic  loss  in  farming  such  land  with  only  1200 
pounds  of  total  phosphorus  in  the  plowed  soil  can  be  appreciated  only  by 
the  man  who  fully  realizes  that  in  less  than  one  generation  the  crop  yields 
could  be  doubled  by  adding  phosphorus, — without  change  of  seed  or  season 
and  with  very  little  more  work  than  is  now  devoted  to>  the  fields. 

Fortunately,  some  definite  field  experiments  have  already  been  conducted 


Pi, ate;  2.  Wheat  in  1911  on  Urbana  Fieed 
CoverXCrops  and  Crop  Residues  Plowed  Under 
Fine-Ground  Rock  Phosphate  Applied 
Average  Yieed,  50. 1 Bushees  Per  Acre 


Soil  Report  No.  6 


[August, 


on  this  most  extensive  type  of  soil,  both  in  Knox  county  and  on  similar 
soil  in  several  other  counties,  as  at  Urbana  in  Champaign  county,  at  Sibley 
in  Ford  county,  and  at  Bloomington  in  McLean  county. 

Results  of  Field  Experiments  at  Urbana 

A three-year  rotation  of  corn,  oats,  and  clover  was  begun  on  the  North 
Farm  at  the  University  of  Illinois  in  1902,  on  three  fields  of  typical  brown 
silt  loam  prairie  land  which,  after  twenty  years  or  more  of  pasturing,  had 
grown  corn  in  1895,  1896,  and  1897  (when  careful  records  were  kept  of 
the  yields  produced)  and  had  then  been  cropped  with  clover  and  grass  on 
one  field,  oats  on  another,  and  oats,  cowpeas,  and  corn  on  the  third  field, 
until  1901. 

As  an  average  of  the  first  three  years  (1902-1904)  phosphorus  increased 


Peate  3.  Wheat  in  1911  on  Urbana  Fieed 
Cover  Crops  and  Farm  Manure  Peowed  Under 
Average  Yieed,  34.2  Bushees  Per  Acre 


Knox  County 


1913] 


Table  3. — Effect  of  Phosphorus  on  Brown  Silt  Loam  at  Urbana 
(Average  increase  per  acre) 


Rotation 

Years 

Corn, 

bu. 

Oats, 

bu. 

Clover, 

tons 

Value  of 
increase1 

Cost  of 
treatment1 

First 

1902,-3,-4 

8.8 

1.9 

.68 

$ 7.73 

$7.50 

Second  

1905,-6,-7 

13.2 

11.9 

.79 

12.93 

7.50 

Third 

1908,-9,-10 

18.7 

8.4 

1.05 

15.37 

7.17 

1Prices  used  are  35  cents  a bushel  for  corn,  30  cents  for  oats,  $6  a ton  for  clover 
hay,  10  and  3 cents  a pound,  respectively,  for  phosphorus  in  bone  meal  and  in  rock 
phosphate. 


the  crop  yields  per  acre  by  .68  ton  of  clover,  8.8  bushels  of  corn,  and  1.9 
bushels  of  oats.  During  the  second  three  years  ( 1905-1907)  it  produced  aver- 
age increases  of  .79  ton  of  clover,  13.2  bushels  of  corn,  and  11.9  bushels  of 
oats.  During  the  third  course  of  the  rotation  (1908-1910)  it  produced  aver- 


Plate  4.  Wheat  in  1911  on  Urbana  Field 
Cover  Crops  and  Farm  Manure  Plowed  Under 
Fine-ground  Rock  Phosphate  Applied 
Average  Yield,  51.8  Bushels  Per  Acre 


10 


Soil  Report  No.  6 


[August, 


age  increases  of  1.05  tons  of  clover,  18.7  bushels  of  corn,  and  8.4  bushels  of 
oats.  For  convenient  reference  the  results  are  summarized  in  Table  3, 

Wheat  is  grown  on  the  University  South  Farm  in  a rotation  experiment 
started  more  recently.  As  an  average  of  the  four  years  1908  to  1911,  raw 
rock  phosphate  (with  no  previous  application  of  bone  meal)  increased  the 
yield  of  wheat  by  10.3  bushels  per  acre.  Here  too,  as  an  average  of  the  four 
years,  the  phosphorus  applied  paid  back  about  twice  its  cost. 

In  the  grain  system  of  farming,  the  yield  of  wheat  in  1911  was  35.2 
bushels  per  acre  where  cover  crops  and  crop  residues  are  plowed  under  with- 
out the  use  of  phosphorus;  but  where  rock  phosphate  is  used  the  average 
yield  was  50.1  bushels.  (See  Plates  1 and  2.) 

In  the  live-stock  system,  the  yield  of  wheat  in  1911  was  34.2  bushels 
where  manure  and  cover  crops  are  used  without  phosphate,  and  51.8  bushels, 
as  an  average,  where  rock  phosphate  is  used  in  addition.  (See  Plates  3 
and  4.) 

These  results  emphasize  the  cumulative  effect  of  permanent  systems  of 
soil  improvement. 

Wheat  has  also  been  grown  on  the  North  Farm  during  the  last  three 
years,  and  the  average  increase  produced  by  phosphorus  (part  in  bone  meal 
and  part  in  raw  phosphate)  has  been  12.4  bushels  per  acre. 

Results  of  Experiments  on  Sibley  Field 

Table  4 gives  the  results  obtained  during  the  past  eleven  years  from  the 
Sibley  soil  experiment  field  located  in  Ford  county  on  the  typical  brown  silt 
loam  prairie  of  the  Illinois  corn  belt. 

Previous  to  1902  this  land  had  been  cropped  with  corn  and  oats  for  many 
years  under  a system  of  tenant  farming,  and  the  soil  had  become  somewhat 
deficient  in  active  organic  matter.  While  phosphorus  was  the  limiting  ele- 
ment of  plant  food,  the  supply  of  nitrogen  becoming  available  annually  was 
but  little  in  excess  of  the  phosphorus,  as  is  well  shown  by  the  corn  yields 
for  1903,  when  phosphorus  produced  an  increase  of  8 bushels,  nitrogen 
without  phosphorus  produced  no  increase,  but  nitrogen  and  phosphorus  to- 
gether increased  the  yield  by  15  bushels. 

After  six  years  of  additional  cropping,  however,  nitrogen  appears  to  have 
become  the  most  limiting  element,  the  increase  in  the  corn  in  1907  having 
been  9 bushels  from  nitrogen  and  only  5 bushels  from  phosphorus,  while 
both  together  produced  an  increase  of  33  bushels.  By  comparing  the  corn 
yields  for  the  four  years  1902,  1903,  1906,  and  1907,  it  will  be  seen  that 
the  untreated  land  has  apparently  grown  less  productive,  whereas  on  land 
receiving  both  phosphorus  and  nitrogen  the  yield  has  appreciably  increased, 
so  that  in  1907,  when  the  untreated  rotated  land  produced  only  34  bushels 
of  corn  per  acre,  a yield  of  72  bushels  (more  than  twice  as  much)  was  pro- 
duced where  lime,  nitrogen,  and  phosphorus  had  been  applied,  altho  the  two 
plots  produced  exactly  the  same  yield  (57.3  bushels)  in  1902. 

Even  in  the  unfavorable  season  of  1910,  the  yield  of  the  highest-producing 
plot  exceeded  that  of  1902,  while  the  untreated  land  produced  less  than  half 
as  much  as  it  produced  in  1902.  The  prolonged  drouth  of  1911  resulted 
in  almost  a failure  of  the  corn  crop,  but  nevertheless  the  effect  of  soil  treat- 
ment is  seen.  Phosphorus  appears  to  have  been  the  first  limiting  element 
again  in  1909,  1910,  and  1911;  while  the  lodging  of  oats,  especially  on  the 


Knox  County 


11 


Table  4. — Crop  Yields  in  Soil  Experiments,  Sibley  Field 


Brown  silt  loam  prairie; 
early  Wisconsin 
glacation 

Corn 

1902 

Corn 

1903 

Oats 

1904 

Wheat 

1905 

Corn 
| 1906 

Corn 
1 1907 

Oats 
| 1908 

Wheat 

1909 

Corn 

1910 

[corn 

[mi 

Oats 
1 1912 

Plot 

Soil  treatment 
applied 

Bushels  per  acre 

101 

None 

57.3 

50.4 

74.4 

29.5 

36.7 

33.9 

25.9 

25.3 

26.6 

20.7 

84.4 

102 

Lime 

60.0 

54.  < 

74.7 

31.7 

39.2 

38.9 

24.7 

28.8 

34.0 

22.2 

85.6 

103 

Lime,  nitrogen  . . 

60.0 

54.3 

77.5 

32.8 

41.7 

48.1 

36.3 

19.0 

29.0 

22  4 

25.3 

104 

Lime,  phosphorus 
Lime,  potassium . 

61.3 

62.3 

92.5 

36.3 

44.8 

43.5 

25.6 

32.2 

52.0 

31.6 

92.3 

105 

55.0 

49.9 

74.4 

30.2 

37.5 

34.9 

22.2 

23.2 

34.2 

21.6 

83.1 

106 

Lime,  nitrogen, 
phosphorus . . . 

57.3 

69.1 

88.4 

45.2 

68.5 

72.3 

45.6 

33.3 

55.6 

35.3 

42.2 

107 

Lime,  nitrogen, 
potassium. . . . 

53 . 3 

51.4 

75.9 

37.7 

39.7 

51.1 

42.2 

25.8 

46.2 

20.1 

55.6 

108 

Lime,  phosphorus, 

60.9 

80.0 

39.8 

41.5 

39.8 

27.2 

28.5 

43.0 

31.8 

79.7 

109 

Lime,  nitrogen, 
phos.,  potas. . . 

58.7 

65.9 

82.5 

48.0 

69.5 

80.1 

52.8 

35.0 

58.  o| 

35.7 

57  2 

110 

Nitro.,  phos., 
potassium  . . . . 

60.0 

60.1 

85.0 

48.5 

63.3 

72.3 

44.1 

30.8 

64  *4  j 

31.5 

54.1 

Average  Increase:  Bushels  per  Acre 


For  nitrogen 

-1.7 

3.4 

.7 

6.4 

14.1 

23.6 

19.3 

.1 

6.4 

1.6 

-40.1 

For  phosphorus 

1.7 

12.1 

10.7 

9.2 

16.5 

15.7 

6.4 

8.1 

16.3 

12.0 

5.4 

For  potassium 

-3.0 

-2.9 

—5.1 

2.4 

—1.5 

1.0 

3.0 

— .2 

2.7 

— .6 

7.5 

For  nitro.,  phos.,  over 

phos 

-4.0 

6.8 

—4.1 

8.9 

23.7 

28.8 

20.0 

1.1 

3.6 

3.7 

-50.1 

For  phos.,  nitro.  over 

nitro 

—2.7 

14.8 

10.9 

12.4 

26.8 

24.2 

9.3 

14.3 

26.6 

12.9 

16.9 

For  potas. , nitro. , phos. 

over  nitro. , phos. . . . 

1.4 

-3.2 

—5.9 

2.8 

1.0 

7.8 

7.2 

1.7 

2.4 

.4 

15.0 

Value  of  Crops  per  Acre  in  Eleven  Years 


Plot 

Soil  treatment  applied 

Total  value  of 
eleven  crops 

Value  of 
increase 

101 

102 

None 

$ 172.73 
184.75 

$ 12.02 

103 

104 

105 

Lime,  nitrogen  

Lime,  phosphorus 

Lime,  potassium 

167.42 

214.50 

173.22 

_ 5.31 
41.77 
.49 

106 

107 

108 

Lime,  nitrogen,  phosphorus 

Lime,  nitrogen,  potassium 

Lime,  phosphorus,  potassium 

233.15 

188.19 

200.37 

60.42 

15.46 

27.64 

109 

110 

Lime,  nitrogen,  phosphorus,  potassium 

Nitrogen,  phosphorus,  potassium ... . 

244.62 

233.51 

71.89 

60.81 

Value  of  Increase  per  Acre  in  Eleven  Years 

Cost  of 
increase 

For  nitrogen 

F or  phosphorus 

F or  nitrogen  and  phosphorus  over  phosphorus 

For  phosphorus  and  nitrogen  over  nitrogen 

For  potassium,  nitrogen,  and  phosphorus  over  nitrogen 

and  TihosrihnriK  

$-17.33 

29.75 

18.65 

65.73 

11.47 

$ 165.00 
27.50 
165.00 
27.50 

27.50 

12 


Soil  Report  No.  6 


[August, 


nitrogen  plots,  in  the  exceptionally  favorable  season  of  1912,  produced  very 
irregular  results. 

In  the  lower  part  of  Table  4 are  shown  the  total  values  per  acre  of  the 
eleven  crops  from  each  of  the  ten  different  plots,  the  amounts  varying  from 
$167.42  to  $244.62;  also  the  value  of  the  increase  produced  in  crop  yields 
above  the  value  of  the  yields  from  the  untreated  land,  corn  being  valued  at 
35  cents  a bushel,  oats  at  30  cents,  and  wheat  at  70  cents.  Phosphorus  with- 
out nitrogen  produced  $29.75  in  addition  to  the  increase  by  lime;  but,  with 
nitrogen,  it  produced  $65.73  above  the  crop  values  where  only  lime 
and  nitrogen  were  used.  The  results  show  that  in  25  cases  out  of  44  the 
addition  of  potassium  decreased  the  crop  yields.  Even  under  the  most  fa- 
vorable conditions,  and  with  no  effort  to  liberate  potassium  from  the  soil  by 
adding  organic  matter,  potassium  paid  back  less  than  half  its  cost. 

By  comparing  Plots  101  and  102,  and  also  109  and  no,  it  will  be  seen 
that  the  average  increase  produced  by  lime  was  $11.55,  or  more  than  $1  an 
acre  a year.  Altho  this  increase  may  have  been  above  normal  on  these  plots 
because  of  the  “condition”  of  the  soil  at  the  beginning,  it  suggests  that  the 
time  is  here  when  limestone  must  be  applied  to  some  of  these  brown  silt  loam 
soils.  While  nitrogen  produced  an  appreciable  increase,  especially  when 
phosphorus  was  provided,  the  only  conclusion  to  be  drawn,  if  we  are  to 
utilize  this  fact  to  advantage,  is  that  the  nitrogen  must  be  secured  from  the  air. 

Results  of  Experiments  on  Bloomington  Field 

Space  is  taken  to  insert  Table  5,  giving  all  of  the  results  thus  far  obtained 
from  the  Bloomington  soil  experiment  field,  which  is  also  located  on  the 
brown  silt  loam  prairie  soil  of  the  Illinois  corn  belt. 

The  general  results  of  the  eleven  years’  work  on  the  Bloomington  field 
tell  much  the  same  story  as  those  from  the  Sibley  field.  The  rotations  dif- 
fered by  the  use  of  clover  and  by  discontinuing  the  use  of  commercial  nitro- 
gen on  the  Bloomington  field  after  1905,  in  consequence  of  which  phosphorus 
without  commercial  nitrogen  (Plot  104)  produced  an  even  larger  increase 
($89.92)  than  was  produced  by  phosphorus  over  nitrogen  ($65.73)  on  the 
Sibley  field  (see  Plots  103  and  106). 

It  should  be  stated  that  a draw  runs  near  Plot  no  on  the  Bloomington 
field,  that  the  crops  on  that  plot  are  sometimes  damaged  by  overflow  or  im- 
perfect drainage,  and  that  Plot  101  occupies  the  lowest  ground  on  the  oppo- 
site side  of  the  field.  In  part  because  of  these  irregularities  and  in  part  be- 
cause only  one  small  application  has  been  made,  no  conclusions  can  be  drawn 
in  regard  to  lime.  Otherwise  all  results  reported  in  Table  5 are  considered 
reliable.  They  not  only  furnish  much  information  in  themselves  but  they 
also  offer  instructive  comparisons  with  the  Sibley  field. 

Wherever  nitrogen  was  provided,  either  by  direct  application  or  by  the  use 
of  legume  crops,  the  addition  of  the  element  phosphorus  produced  very  marked 
increases,  the  average  yearly  increase  for  the  Bloomington  field  being  worth 
$7.11  an  acre.  This  is  $4.61  above  the  cost  of  the  phosphorus  in  200  pounds 
of  steamed  bone  meal,  the  form  in  which  it  was  applied  to  the  Sibley  and 
Bloomington  fields.  On  the  other  hand,  the  use  of  phosphorus  without  nitro- 
gen will  not  maintain  the  fertility  of  the  soil  (see  Plots  104  and  106,  Sibley 
field).  As  the  only  practical  and  profitable  method  of  supplying  the  nitrogen, 
a liberal  use  of  clover  or  other  legumes  is  suggested,  the  legume  to  be  plowed 


Knox  County 


13 


W3] 


Tabus  5 Crop  Yields  in  Soil  Experiments,  Bloomington  Field 


Brown  silt  loam  prairie; 
early  Wisconsin 
glaciation 

Corn 

1902 

Corn 

1903 

Oats 

1904 

■Wheat 

1905 

Clover 

1906 

Corn 

1907 

Corn 

1908 

Oats 

1909 

Clover2 

1910 

Wheat 

1911 

Corn 
1 1912 

1 lou  | 

Soil  treatment 
applied 

Bushels  or  tons  per  acre 

101 

None 

30.8 

63.9 

54.8 

30  8 

.39 

60.8 

40.3 

46.4 

1.56 

22.5 

55.2 

102 

Eime 

37.0 

60.3 

60.8 

28.8 

.58 

63.1 

35.3 

53.6 

1.09 

22.5 

47.9 

103 

Lime,  crop  res. 1 .. . . 

35.1 

59.5 

69.8 

30.5 

1 .46 

64.3 

36.9 

49.4 

(.83) 

25.6 

62.5 

104 

Lime,  phosphorus.  . 

41.7 

73.0 

72.7 

39.2 

1.65 

82.1 

47.5 

63.8 

4.21 

57.6 

74.5 

105 

Lime,  potassium  . . . 

37.7 

56.4 

62. 5|  33.2 

.51 

64.1 

36.2 

45.3 

1 126 

21.7 

57.8 

106 

Lime,  residues,1 

phosphorus 

43.9 

77.6 

85.3 

50.9 

3 

78.9 

45.8 

72.5 

(1.67) 

60.2 

86.1 

107 

Lime,  residues,1 

potassium 

40.4 

58.9 

66.4 

29.5 

.81 

64.3 

31.0 

51.1 

(.33) 

27.3 

58.9 

108 

Lime,  phosphorus, 

potassium 

50.1 

74.8 

70.3 

37.8 

2.36 

81.4 

57.2 

59.5 

3.27 

54.0 

79.2 

109 

Lime,  res.,1  phos., 

52.7 

80.9 

90.5 

51.9 

3 

88.4 

58.1 

64.2 

(-42) 

60.4 

83.4 

potassium 

110 

Res.,  phosphorus, 

52.3 

73.1 

71.4 

51.1 

3 

78.0 

51.4 

55.3 

(.60) 

61.0 

78.3 

potassium 

1 

Average  Increase:  Bushels  or  Tons  per  Acre 

For  residues  

1.4 

3.1 

11.4 

5.9 

-.96 

1.3 

-1.1 

3.7 

-1.64 

4.4 

7.9 

For  phosphorus 

9.5 

17.8 

14.8 

14.4 

.41 

18.8 

18.0 

15.1 

1.51 

33.9 

24.0 

For  potassium 

5.8 

.2 

.3 

.7 

.25 

2.4 

4.2 

-4.8 

-.63 

-.6 

2.1 

For  res.,phos.overphos. 

2.2 

4.6 

12.6 

11.7 

— .65 

-3.2 

-1.7 

8.7 

-2.25 

2.6 

11.6 

For  phos.,res.  over  res. 

8.8 

18.1 

15.5 

20.4 

-1.46 

14.6 

8.9 

23.1 

.84 

34.6 

23.6 

For  potas.,  res.,  phos. 

over  res.,  phos 

8.8 

3.3 

5.2 

1.0 

.00 

9.5 

12.3 

-8.3 

-1.25 

.'2 

-2.7 

Value  of  Crops  per  Acre  in  Eleven  Years 


O 

ru 

Soil  treatment  applied 

Total  value  of 
eleven  crops 

Value  of 
increase 

101 

None 

$167.22 

102 

Lime 

165.52 

-$1.70 

103 

Lime,  residues 

173.17 

5.95 

104 

Lime,  phosphorus 

255.44 

88.22 

105 

Lime,  potassium  

169.66 

2.44 

106 

Lime,  residues,  phosphorus 

251.43 

84.21 

107 

Lime,  residues,  potassium 

170.57 

3.26 

108 

Lime,  phosphorus,  potassium 

256.92 

89.70 

109 

Lime,  residues,  phosphorus,  potassium 

254.76 

87.54 

110 

Residues,  phosphorus,  potassium 

236.66 

69.44 

Value  of  Increase  per  Acre  in  Eleven  Years 

Cost  of 
increase 

For  residues 

$ 7.65 

7 

For  phosphorus 

89.92 

$27.50 

For  residues  and  phosphorus  over  phosphorus 

-4.01 

? 

For  phosphorus  and  residues  over  residues 

For  potassium,  residues,  and  phosphorus  over  residues 

78.26 

27.50 

and  phosphorus 

3.33 

27.50 

‘Commercial  nitrogen  was  used  1902-1905. 

®The  figures  in  parentheses  mean  bushels  of  seed;  the  others,  tons  of  hay. 
®Clover  smothered  by  previous  wheat  crop. 


14  Soil  Report  No.  6 [August, 

under  either  directly  or  as  manure,  preferably  in  connection  with  the  phos- 
phorus applied,  especially  if  raw  rock  phosphate  is  used. 

From  the  soil  of  the  best  treated  plots,  160  pounds  per  acre  of  phos- 
phorus, as  an  average,  were  removed  in  the  eleven  crops.  This  is  equal  to 
more  than  13  percent  of  the  total  phosphorus  contained  in  the  surface  soil  of 
an  acre  of  the  untreated  land.  In  other  words,  if  such  crops  could  be  grown 
for  eighty  years,  they  would  require  as  much  phosphorus  as  the  total  supply 
in  the  ordinary  plowed  soil.  The  results  plainly  show,  however,  that  without 
the  addition  of  phosphorus  such  crops  cannot  be  grown  year  after  year. 
Where  no  phosphorus  was  applied,  the  crops  removed  only  107  pounds  of 
phosphorus  in  the  eleven  years,  which  is  equivalent  to  only  9 percent  of  the 
total  amount  ( 1,200  pounds)  in  the  surface  soil  at  the  beginning  ( 1902).  The 
total  phosphorus  applied  from  1902  to  1912,  as  an  average  of  all  plots  where 
it  was  used,  amounted  to  275.  pounds  per  acre  and  cost  $27.50.  This  paid 
back  $84.91,  or  300  percent  on  the  investment;  whereas  potassium,  used  in 
the  same  number  of  tests  and  at  the  same  cost,  paid  back  only  $1.59  per  acre 
in  the  eleven  years,  or  less  than  6 percent  of  its  cost.  Are  not  these  results 
to  be  expected  from  the  composition  of  the  soil  and  the  requirements  of 
crops?  (See  Table  2,  page  7,  and  also  Table  A in  the  Appendix.) 

Nitrogen  was  applied  to  this  field  in  commercial  form  only,  from  1902 
to  1905;  but  clover  was  grown  in  1906  and  1910,  and  a catch  crop  of  cow- 
peas  after  the  clover  in  1906.  The  cowpeas  were  plowed  under  on  all 
plots,  and  the  1910  clover  (except  the  seed)  was  plowed  under  on  five  plots 
(103,  106,  107,  109,  and  no).  Straw  and  corn  stalks  have  also  been  re- 
turned to  these  plots  in  recent  years.  The  effect  of  returning  these  residues 
to  the  soil  is  already  appreciable  (an  average  increase  of  4.4  bushels  of  wheat 
in  1911  and  7.9  bushels  of  corn  in  1912)  and  probably  will  be  more  marked 
on  subsequent  crops.  Indeed,  the  large  crops  of  corn,  oats,  and  wheat 
grown  on  Plots  104  and  108  during  the  eleven  years  drew  their  nitrogen 
very  largely  from  the  natural  supply  in  the  organic  matter  of  the  soil. 

The  roots  and  stubble  of  clover  contain  no  more  nitrogen  than  the  entire 
plant  takes  from  the  soil  alone,  but  they  decay  rapidly  in  contact  with  the  soil 
and  probably  hasten  the  decomposition  of  the  soil  humus  and  the  consequent 
liberation  of  the  soil  nitrogen.  But  of  course  there  is  a limit  to  the  reserve 
stock  of  humus  and  nitrogen  remaining  in  the  soil,  and  the  future  years  will 
undoubtedly  witness  a gradually  increasing  difference  between  Plots  104 
and  106  and  between  Plots  108  and  109,  in  the  yields  of  grain  crops. 

In  Plate  5 are  shown  graphically  the  relative  values  of  the  eleven  crops 
for  the  eight  comparable  plots,  Nos.  102  to  T09.  The  cost  of  the  phosphorus 
is  indicated  by  that  part  of  the  diagram  ab'ove  the  short  crossbars.  It  should 
be  kept  in  mind  that  no  value  is  assigned  to  clover  plowed  under  except  as 
it  reappears  in  the  increase  of  subsequent  crops.  Plots  106  and  109  are 
heavily  handicapped  because  of  the  clover  failure  on  those  plots  in  1906  and 
the  poor  yield  of  clover  seed  in  1910,  whereas  Plots  104  and  108  produced 
a fair  crop  in  1906  and  a very  large  crop  in  1910.  As  an  average,  Plots  106 
and  109  are  only  $3.09  behind  Plots  104  and  108  in  the  value  of  the  eleven 
crops  harvested,  and  this  would  have  been  covered  by  about  V2  bushel  more 
clover  seed  in  1906  or  1910,  or  it  may  be  covered  by  10  bushels  more  corn 
in  1913.  The  values  from  Plots  T03  and  107  average  $4.28  more  than  the 
values  from  Plots  102  and  105.  (See  also  table  on  last  page  of  cover.) 

(R  stands  for  residues;  P,  for  phosphorus,  and  K,  for  potassium  Kalinin. ) 


Knox  County 


L5 


1913] 


102 

103 

104 

105 

106 

107 

108 

109 

0 

R 

P 

K 

RP 

RK 

PK 

RPK 

$165.52 

$173.17 

$255.44 

$169.66 

$251.43 

$170.57 

$256.92 

$254.76 

Plate  5.  Crop  Values  for  Eleven  Years, 
Bloomington  Experiment  Field 


Results  of  Field  Experiments  at  Galesburg 

In  Tables  6,  7,  and  8 are  reported  in  detail  the  results  obtained  from  the 
University  of  Illinois  soil  experiment  field  near  Galesburg,  on  the  line  be- 
tween Knox  and  Warren  counties,  on  the  brown  silt  loam  prairie  soil  of  the 
upper  Illinois  glaciation. 

A six-year  rotation  has  been  practiced  on  this  field  since  1904.  During 
the  first  six  years  the  order  of  cropping  was  corn,  com,  oats,  wheat,  followed 
by  two  years  of  clover  and  timothy.  Since  then  the  rotation  has  been  corn, 
com,  oats,  clover,  wheat,  clover.  There  are  only  three  independent  series  of 
plots,  so  that  while  corn  is  grown  every  year  the  other  crops  are  harvested 
only  in  alternate  years,  altho  clover  should  be  on  the  field  every  year,  either 
in  the  stubble  of  the  oats  and  wheat  or  as  a regular  crop. 

Each  series  contains  twenty  individual  fifth-acre  plots  2 rods  wide  and 
16  rods  long,  with  half-rod  division  strips  cultivated  and  cropped  between 
the  plots,  a quarter-rod  border  cultivated  and  cropped  surrounding  each 
series,  and  grass  strips  about  two'  rods  wide  between  the  series  and  surround- 
ing the  experiment  field.  The  soil  treatment  for  the  individual  plots  is 
indicated  in  Tables  6,  7,  and  8. 

Limestone  was  applied  in  small  amount  ( 1300  pounds  per  acre)  to  the  first 
fifteen  plots  in  each  series  in  1904.  No  further  application  was  made  until 
the  spring  oF  1912,  when  4 tons  per  acre  was  applied  to  Plots  1 to  15  of  Series 


16 


Soil  Report  No.  6 


[August, 


Table  6. — Crop  Yields  in  Soil  Experiments,  Galesburg  Field:  Series  100 


Brown  silt  loam  prairie; 
upper  Illinois  glaciation 

Corn 

1904 

Corn  ^ 
1905 

Oats 

1906 

'wheat 

1907 

Clo- 
ver1 
| 1908 

Timo- 

thy1 

1909 

Corn 

1910 

Corn 

1911 

Oats 

1912 

Plot 

Soil  treatment  applied 

Bushels 

> or  tons  per  acre 

101 

102 

103 

104 

105 

Lime  

Residues,  lime 

Manure,  lime 

Cover  crop,  manure,  lime . . . 
Lime 

63.8 

67.3 

64.7 

65.3 

74.7 

52.5 

49.8 
48.1 

46.5 

54.9 

53.8 

53.6 

50.3 

46.7 

52. 3 

34.0 
41.4 
31.6 
32.8 

35.1 

7-96) 

2.59 

2.61 

2.80 

2.04 
(3.83) 

1.83 

1.70 

2.05 

59.8 

72.6 

77.6 

77.9 
66.2 

66.5 

75.1 

81.0 

78.9 

67.4 

53.3 

56.9 

60.0 

70.2 

60.8 

106 

Lime,  phosphorus 

78.2 

66.1 

53.9 

41.9 

3.18 

2.58 

72.4 

79.4 

68.6 

107 

Residues,  lime,  phosphorus 

75.9 

63.1 

55.0 

41.3 

(.67) 

(4.92) 

78.0 

83.8 

65.2 

108 

Manure,  lime,  phosphorus.. 

72.6 

61.1 

54.2 

37.9 

3.18 

2.36 

74.6 

79.8 

77.3 

109 

Cover  crop,  manure,  lime, 

phosphorus 

74.1 

60.0 

54.2 

40.0 

3.15 

2.33 

74.0 

79.1 

74.4 

110 

Lime 

72.4 

58.8 

50.5 

32.7 

2.65 

1.74 

61.5 

59.2 

54.5 

111 

Lime,  phosphorus,  po- 

tassium   

81.2 

72.3 

53.9 

36.6 

3.21 

2.42 

74.5 

81.1 

70.9 

112 

Residues,  lime,  phosphorus, 

potassium 

82.3 

71.0 

59.4 

41.1 

(.58) 

(5.00) 

81.9 

83.7 

59.5 

113 

Manure,  lime,  phosphor- 

us, potassium 

77.1 

72  2 

52.8 

36.1 

3.45 

2.49 

77.6 

82.4 

74.4 

114 

Cover  crop, manure, lime, 

phos.,  potassium 

89.4 

69.9 

54.5 

38.7 

3.36 

2.55 

75.9 

85.0 

70.0 

115 

Lime 

81.2 

68.1 

62.8 

36.8 

2.99 

2.19 

59.4 

67.3 

53.0 

116 

Residues 

77.1 

61.8 

57.3 

38.2 

(1.17) 

(5.33) 

70.6 

68.9 

52.0 

117 

Residues,  phosphorus 

79.4 

64.2 

60.0 

36.2 

(1.25) 

(5.50) 

75.0 

77.5 

66.1 

118 

Residues,  phosphorus, 

potassium 

82.3 

70.8 

52.0 

40.9 

(1.38) 

(4.75) 

78.3 

78.4 

68.1 

119 

Residues,  lime,  nitrogen, 

phos.,  potassium 

87.1 

76.3 

66.2 

46.0 

(1.08) 

(5.00) 

74.8 

79.3 

67.3 

120 

None 

82.9 

65.1 

65.3 

45.8 

3.04 

2.82 

72.7 

67.4 

70.2 

Increase  for  residues. 

—2.19 

— .89 

5.9 

4.3 

—7.3 

Increase  for  manure 

7.7 

5.4 

6.3 

Increase  for  phosphorus 

6.2 

10.7 

3.4 

3.6 

.26 

.42 

1.8 

5.7 

10.3 

Increase  for  potassium 

6.4 

8.3 

—.9 

— 8 

.11 

— .01 

2.8 

2.2 

—1.7 

Increase  for  nitrogen 

4.8 

5.5 

14.2 

5.1 

-(,30) 

(.25) 

-3.5 

.9 

—.8 

'The  figures  in  parentheses  in  these  columns  represent  bushels  of  seed;  the  others, 
tons  of  hay. 


300.  Thus  far  no  apparent  effect  has  been  produced,  but  further  experiment 
with  liberal  applications  may  show  results.  Plots  1 to  15  in  Series  100  and 
200  were  given  4 tons  per  acre  in  the  spring  of  1913. 

The  “residues”  include  the  straw  and  com  stalks,  all  clover  except  the 
seed,  and  legume  cover  crops,  such  as  cowpeas,  soybeans,  or  vetch,  seeded  in 
the  corn  at  the  last  cultivation.  They  are  returned  to  certain  plots  to  supply 
nitrogen  and  organic  matter  in  a system  of  grain  farming.  This  system  was 
not  fully  under  way  on  all  series  until  1911,  as  may  be  seen  from  the  lower 
parts  of  Tables  6,  7,  and  8,  so  that  as  yet  no  conclusions  regarding  this  treat- 
ment are  justified,  except  that  an  abundance  of  organic  matter  is  thus  pro- 
vided. Whether  the  value  of  the  clover  plowed  under  will  ultimately  reappear 
in  subsequent  yields  of  grain  and  seed,  must  be  determined  by  the  further  ac- 
cumulation of  data.1 


'Alsike  clover  promises  to  yield  the  better  returns  in  seed,  altho  in  some  cases  seed  has 
been  threshed  from  both  the  first  and  second  cuttings  of  the  red  clover.  It  is  quite  possible 
that  better  average  results  would  be  secured  by  regularly  removing  the  first  cutting  of  red 
clover,  with  the  purpose  of  threshing  it  for  seed,  as  well  as  the  second  cutting  if  found 


Knox  County 


17 


1913 ] 


Table  7 Crop  Yields  in  Soil  Experiments,  Galesburg  Field:  Series  200 


Brown  silt  loam  prairie; 
upper  Illinois  glaciation 

Oats 

1904 

Wheat 

1905 

[clover 

1906 

. Timo- 
thy 
1907 

Corn 

1908 

[corn 
1 1909 

Oats 

1910 

Clover 

1911 

Wheat 

1912 

Plot 

Soil  treatment  applied 

Bushels  or  tons 

per  acre 

201 

Lime 

57.5 

40.5 

. 72 

2.30 

79.8 

54.1 

48.0 

1.39 

17.5 

202 

Residues,  lime 

55.0 

40.0 

.63 

1.31 

78.8 

51.9 

43.3 

21.1 

203 

Manure,  lime 

52.5 

38.5 

.57 

2.55 

101.3 

65.6 

50.6 

2.64 

21.7 

204 

Cover  crop,  manure, 

lime 

55. ( 

40.2 

.63 

2.73 

102.7 

66.8 

53.0 

2.32 

19.6 

205 

Lime 

67.5 

42.2 

1.22 

2.84 

86.3 

54.4 

44.4 

2.29 

18.2 

206 

Lime,  phosphorus 

62.5 

41.3 

1.36 

3.27 

99.6 

59.1 

55.5 

2.42 

27.3 

207 

Residues,  lime,  phos- 

phorus. . 

57.5 

42.2 

.90 

1.79 

105.6 

49.4 

48.6 

27.3 

208 

Manure,  lime,  phos- 

phorus 

60.0 

40.0 

.91 

3.18 

106.6 

69.8 

58.6 

2.30 

27.3 

209 

Cover  crop,  manure, 

lime,  phos.. 

50.0 

39.0 

.91 

3.16 

105.8 

75.7 

60.3 

2.03 

27.8 

210 

Lime 

57.5 

37.5 

.69 

2.46 

84.5 

57.8 

42.: 

1.14 

12.2 

211 

Lime,  phosphorus,  po- 

tassium   

55.0 

38.7 

1.31 

3.38 

95.7 

67.0 

55.3 

2.01 

28.2 

212 

Residues,  lime,  phos- 

phorus, potassium . . 

65.0 

39.3 

1.40 

2.15 

103.3 

57.5 

53.8 

28.3 

213 

Manure,  lime,  phos- 

phorus, potassium.. 

65.0 

41.5 

1.79 

3.62 

98.1 

69.8 

58.3 

2.55 

25.9 

214 

Cover  crop,  manure, 

lime,  phos.,  potas. . . 

62.5 

40.7 

i:si 

3.48 

102.8 

73.3 

62.8 

2.46 

25.3 

215 

Lime 

60.0 

35.5 

.83 

2.33 

84.1 

58.2 

41.6 

.98 

8.8 

216 

Residues 

72.5 

37.0 

.82 

1.37 

87.3 

54.8 

38.6 

11.8 

217 

Residues,  phosphorus . . 

57.5 

38.7 

.85 

1.44 

98.6 

49.6 

43.4 

22.1 

218 

Residues,  phosphorus, 

potassium 

50.0 

40.7 

1.51 

2.17 

99.0 

43.0 

46.3 

28.3 

219 

Residues,  lime,  nitro- 

gen, phos.,  potas.  . . . 

57.5 

37.7 

1.21 

1.98 

109.6 

47.2 

57.2 

27.3 

220 

None 

55.0 

39.5 

.71 

2.49 

88.3 

49.5 

38.1 

1.00 

15.6 

Increase  for  residues 

—3.1 

—1.70 

0.0 

Increase  for  manure 

7 . 7 

8.3 

2.9 

.56 

.6 

Increase  for  phosphorus. . . . 

-3.0 

.7 

.21 

.41 

12.0 

2.0 

7.3 

— .17 

7.7 

Increase  for  potassium 

2.0 

— .1 

.52 

.39 

—3.5 

1.4 

2.0 

.09 

.8 

Increase  for  nitrogen 

7.5 

—3.0 

— .30 

— .19 

10.6 

4.2 

10.9 

—1.0 

Farm  manure  is  applied  to  certain  plots  (see  tables)  in  proportion  to  their 
previous  average  crop  yields,  that  is,  as  many  tons  of  manure  are  applied 
to  each  plot  as  there  were  tons  of  average  air-dry  produce  removed  from  the 
corresponding  plots  during  the  previous  rotation;  but  no  manure  was  used 
until  crops  had  been  grown  for  four  years  and  the  data  had  been  thus  ac- 
cumulated from  which  to  compute  the  proper  applications  of  manure.  The 
live-stock  system  was  not  fully  under  way  on  all  series  until  1912  (see  lower 
parts  of  tables),  when  the  average  increase  from  the  manure  varied  from  3^ 
bushel  of  wheat  to  nearly  17  bushels  of  corn. 

On  Plots  4,  9,  and  14  cover  crops  are  grown  as  indicated  in  the  tables, 
but  the  results  thus  far  secured  do  not  justify  advising  this  practice,  as  may 
be  seen  by  comparing  these  plots  with  Plots  3,  8,  and  13,  respectively. 

advisable.  Some  splendid  seed  crops  have  been  secured  from  the  second  cutting  when  the 
hrst  was  clipped  and  left  on  the  land,  hut  under  other  seasonal  conditions  the  second  crop 
has  been  a failure.  In  such  cases,  altho  the  apparent  effect  is  a total  loss  of  the  clover 
crop,  at  least  part  of  this  apparent  loss  is  recovered  in  subsequent  crops  of  grain.  It  should 
never  be  forgotten  that  the  purpose  of  this  system  is  to  enable  the  grain  farmer  to  maintain 
. fertility  of  his  soil,  even  tho  some  other  system  which  he  may  not  be  prepard  to  adopt 
might  be  more  profitable.  v 


18 


Soil  Report  No.  6 


[August, 


Table  8. — Crop  Yields  in  Soil  Experiments,  Galesburg  Field:  Series  300 


Brown  silt  loam  prairie; 
upper  Illinois  glaciation 

Tim- 

othy 

1904 

Tim- 

othy 

1905 

Cornjcornl 
1906  1907  I 

Oats 

1908 

Wheat 

1909 

Wheat 

1910 

Clover 

1911 

Corn 

1912 

Plot 

Soil  treatment  applied 

Bushels 

or  tons  per  acre 

301 

Lime 

1.36 

1.54 

66.8 

75.9 

28.6 

31.7 

16.2 

2.17 

70.8 

302 

Residues,  lime 

1.38 

1.59 

68.6 

77.7 

26.6 

33.8 

19.4 

89.6 

303 

Manure,  lime 

1.30 

1.92 

72.0 

80.3 

28.3 

36.3 

19.6 

2.57 

104.3 

304 

Cover  crop,  manure, 

lime 

1.38 

2.02 

75.6 

83.1 

26.1 

40.4 

22.3 

2.03 

103.3 

305 

Lime 

1.20 

1.75 

70.5 

78.3 

22.5 

36.6 

21.2 

1.83 

92.1 

306 

Lime,  phosphorus 

1.21 

1.65 

69.7 

84.4 

32.7 

40.6 

22.2 

2.64 

98.2 

307 

Res., lime,  phosphorus 

1.16 

1.55 

74.0 

84.1 

27.5 

41.2 

24.1 

103.2 

308 

Manure,  lime,  phos- 

phorus 

1.25 

1.63 

73.9 

86.1 

33.9 

39.7 

21.6 

3.25 

107.9 

309 

Cover  crop,  manure, 

lime,  phosphorus . . . 

1.55 

2.03 

83.9 

87.8 

28.9 

44.9 

24.9 

3.13 

106.0 

310 

Lime 

1.75 

2.25 

84.3 

85.6 

31.6 

39.8 

22.4 

2.74 

93.0 

311 

Lime,  phosphorus,  po- 

tassium  

2.10 

2.41 

86.9 

87.8 

32.3 

44.3 

24.5 

3.59 

101.9 

312 

Residues,  lime,  phos- 

phorus, potassium.. 

1.55 

1.91 

75.8 

81.2 

25.9 

41.8 

23.2 

98.4 

313 

Manure,  lime,  phos- 

phorus, potassium. . 

1.16 

1.53 

68.4 

77.9 

31.3 

35.8 

23.0 

3.28 

108.8 

314 

Cover  crop,  manure, 

lime,  phos.,  potas. . . 

1.50 

1.52 

70.6 

81.7 

27.7 

42.0 

23.1 

3.57 

106.9 

315 

Lime 

1.90 

1.97 

74.1 

85.1 

30.6 

36.8 

21.6 

2.47 

90.6 

316 

Residues 

1.82 

1.82 

67.7 

80.6 

26.7 

34.2 

22  9 

82.1 

317 

Residues,  phosphorus. 

1.95 

2.00 

59.1 

83.3 

31.1 

44.9 

27.0 

99.2 

318 

Residues,  phosphorus, 

potassium 

2.65 

2.18 

66.8 

73.6 

25.8 

43.3 

29.1 

113.2 

319 

Residues,  lime,  nitro- 

gen, phos.,  potas. . . . 

4.15 

2.37 

71.2 

84.7 

32.7 

43.8 

24.9 

104.1 

320 

None 

1.46 

1.56 

59.6 

72.8 

31.3 

28.5 

15.8 

1.46 

79.1 

Increase  for  residues 

—2.46 

5.8 

Increase  for  manure  .... 

16.7 

Increase  for  phosphorus 

.01 

-.05 

1.2 

5.1 

4.8 

6.0 

2.9 

.86 

8.6 

Increase  for  potassium 

.37 

.14 

1.6 

—4.7 

— 2.2 

-.8 

.6 

.47 

2.9 

Increase  for  nitrogen 

1.50 

.19 

4.4 

11.1 

6.9 

.5 

-4.2 

-9.1 

At  the  beginning  of  this  experiment  this  field  was  all  in  timothy  sod. 
Series  300  was  not  broken  during  the  first  two  years,  but  ton  of  raw  rock 
phosphate  per  acre  was  applied  as  top-dressings.  This  produced  practically  no 
effect, — a result  to  be  expected.  A ton  of  phosphate  per  acre  applied  to 
Series  200  produced  no  effect  on  the  oats  seeded  on  timothy  sod  in  1904  and 
but  little  effect  on  the  wheat  which  followed  in  1905.  Beginning  with  Series 
ico  in  1904,  Series  300  in  1906,  and  Series  200  in  1908,  the  regular  plan  has 
been  to  apply  il/>  tons  of  raw  rock  phosphate  (375  pounds  of  phosphorus)  per 
acre  every  six  years  before  plowing  for  corn,  in  addition  to  the  partial  appli- 
cations made  as  stated  above.  This  plan  has  been  followed  essentially,  and 
will  be  continued  until  the  phosphorus  content  of  the  plowed  soil  is  at  least 
doubled,  but  ultimately  the  amounts  applied  for  each  rotation  will  be  reduced 
to  supply  only  about  as  much  as  is  removed  in  the  crops  grown,  and  of  course 
the  annual  expense  for  this  element  will  then  decrease  accordingly. 

Potassium  is  applied  in  the  form  of  potassium  sulfate,  100  pounds  per 
acre  of  the  sulfate  (containing*  42  pounds  of  potassium)  being  used  for  each 
year  in  the  rotation.  The  application  is  made  only  in  connection  with  the 


Knox  County 


19 


1913] 


phosphate  in  order  to  ascertain  whether  its  use  in  this  way  is  profitable,  there 
being  no  doubt  that  it  would  be  unprofitable  if  used  alone. 

In  order  to  help  settle  the  question  whether  commercial  nitrogen  could 
be  used  with  profit,  Plot  19  has  received  nitrogen  at  the  rate  of  25  pounds 
per  acre  per  annum.  Nearly  the  total  amount  for  the  first  four  years  was 
applied  in  1904,  but  since  1907  the  applications  have  been  made  annually. 
The  nitrogen  has  been  applied  in  addition  to  crop  residues,  phosphorus,  and 
potassium,  but  without  limestone. 


Table  9. — Galesburg  Experiment  Field:  Financial  Statement 
(Value  of  increase  from  three  acres) 


Series  100 

Series  200 

Series  300 

Y ears 

Corn 

Oats 

Grass 

1904 

Corn 

Wheat 

Grass 

1905 

Oats 

Clover 

Corn 

1906 

Wheat 

Grass 

Corn 

1907 

Clover 

Corn 

Oats 

1908 

1 

Grass 

Corn 

Wheat 

1909 

Corn 

Oats 

Wheat 

1910 

Corn 

Clover 

Clover 

1911 

Oats 

Wheat 

Corn 

1912 

Aver- 

age 

1907 

to 

1912 

For  residues . . 
For  manure. . . 
Forphosph’r’s 
For  potassium 
For  nitrogen. . 

$ 1.33 
S.06 
12.93 

$ 3.93 
3.67 
.97 

$2.70 

3.41 

4.00 

$6 . 77 
.14 
6.31 

$13.14' 

2.701 

7.20 

-1.22 

3.98 

$-5.34> 
2. 90' 
7.42 
-.13 
3.32 

> 1.13? 
3.57* 
4.85 
2.00 
-.90 

$23.46 

5.2S2 

6.14 

4.13 

.31 

$ -.16 
8.16 
11.49 
1.06 
-4.12 

$7.31 

1.00 

1.48 

1 One  crop  only. 
2Two  crops  only. 


In  Table  9 is  given  a financial  summary  of  the  results  thus  far  secured 
from  the  Galesburg  field.  Three  facts  are  clearly  brought  out  by  the  data : 

First. — Commercial  nitrogen  at  15  cents  a pound  has  never  paid  its  cost, 
and  as  the  system  of  providing  “home-grown”  nitrogen  in  crop  residues  has 
developed,  the  effect  of  commercial  nitrogen  has  decreased,  so  that  as  an 
average  of  the  last  five  years  it  has  paid  back  only  4 percent  of  its  annual 
cost. 

Second. — Potassium,  likewise,  has  never  paid  its  cost,  but  during  the 
early  years,  when  no  adequate  provision  was  made  for  decaying  organic 
matter,  the  soluble  potassium  salt  produced  a very  marked  effect,  due  in  part 
no  doubt  to  the  fact  that  it  helped  to  dissolve  and  make  available  the  raw 
phosphate  always  applied  with  it.  With  the  subsequent  increase  in  decaying 
organic  matter,  the  effect  of  potassium  was  greatly  reduced.  As  an  average 
of  the  last  six  years,  potassium  costing  $7.50  has  paid  back  only  $1. 

Third.— Phosphorus  applied  in  fine-ground  natural  rock  phosphate  in 
part  as  top-dressing,  and  with  no  adequate  provision  for  decaying  organic 
matter,  paid  only  47  percent  on  the  investment  as  an  average  of  the  first  three 
years.  But  it  should  be  kept  in  mind  that  the  word  investment  is  here  used 
in  its  proper  sense,  for  the  phosphorus  removed  in  the  increase  produced  was 
less  than  2 percent  of  the  amount  applied,  and  that  removed  in  the  total  crops, 
less  than  one-third.  During  the  last  six  years,  however,  the  phosphorus  has 
paid  130  percent  on  the  investment,  even  tho  two-thirds  of  the  application  re- 
mains to  positively  enrich  the  soil. 

The  results  from  the  Galesburg  experiment  field  furnish  some  interest- 
ing and  valuable  illustrations  of  the  danger  of  drawing  incorrect  conclusions 
from  field-culture  experiments  conducted  for  a short  time  only  and  without 
comprehensive  knowledge  of  the  factors  involved.  Thus,  the  first  year  the 
effect  of  potassium  ($5.06)  was  four  times,  and  that  of  nitrogen  ($12.93) 
ten  times  as  great  as  the  effect  of  phosphorus  ($1.33)  ; whereas  in  the  last 


20 


Soil  Report  No.  6 


[August, 


year  the  effect  of  phosphorus  ($11.49)  was  eleven  times  that  of  potassium 
($1.06),  while  commercial  nitrogen  applied  in  addition  to  the  crop  residues 
appears  to  have  been  detrimental.  These  facts  only  support  the  following 
statement  quoted  on  page  208  of  Bulletin  123,  “The  Fertility  in  Illinois  Soils” : 

“In  considering  the  general  subject  of  culture  experiments  for  determining  fertilizer 
needs,  emphasis  must  be  laid  on  the  fact  that  such  experiments  should  never  be  accepted 
as  the  sole  guide  in  determining  future  agricultural  practice.  If  the  culture  experiments  and 
the  ultimate  chemical  analysis  of  the  soil  agree  in  the  deficiency  of  any  plant-food  element, 
then  the  information  is  conclusive  and  final ; but  if  these  two  sources  of  information  dis- 
agree, then  the  culture  experiments  should  be  considered  as  tentative  and  likely  to  give 
way  with  increasing  knowledge  and  improved  methods  to  the  information  based  on  chem- 
ical analysis,  which  is  absolute.”1 


The  Subsurface  and  Subsoje 

In  Tables  10  and  11  are  recorded  the  amounts  of  plant  food  in  the  sub- 
surface and  the  subsoil,  but  it  should  be  remembered  that  these  supplies  are  of 
little  value  unless  the  top  soil  is  kept  rich.  Probably  the  most  important  in- 
formation contained  in  these  tables  is  that  the  most  valuable  upland  timber 
soil  (yellow-gray  silt  loam)  is  usually  more  strongly  acid  in  the  subsurface 
and  the  subsoil  than  in  the  surface,  thus  emphasizing  the  importance  of  having 
plenty  of  limestone  in  the  surface  soil  to  neutralize  the  acid  moisture  which 
rises  from  the  lower  strata  by  capillary  action  during  times  of  partial 
drouth,  which  are  critical  periods  in  the  life  of  such  plants  as  clover.  Thus, 
while  the  common  brown  silt  loam  prairie  soil  is  practically  neutral,  the  upland 
timber  soil  of  similar  topography  is  already  in  need  of  limestone;  and,  as 
already  explained,  it  is  much  more  deficient  in  phosphorus  and  nitrogen  than 
is  the  common  prairie  soil. 

'Taken  from  “Culture  Experiments  for  Determining  Fertilizer  Needs,”  by  C.  G.  H.  in 
Cyclopedia  of  American  Agriculture,  Volume  I,  page  475. 


Knox  County 


21 


1913] 


Tab ue  10. — Fertility  in  the  Soils  oe  Knox  County 
Average  pounds  per  acre  in  4 million  pounds'  of  subsurface  (about  673  to  20  inches) 


Soil 

Total 

Total 

Total 

Total 

Total 

Total 

Lime- 

Lime- 

type 

Soil  type 

organic 

nitro- 

phos- 

potas- 

magne- 

cal- 

stone 

stone 

No. 

carbon 

gen 

phorus 

sium 

sium 

cium 

present 

requir’d 

Upland  Prairie  Soils 


526 

Brown  silt  loam  82  720 

6 900 

1 960 

66  060 

22  590 

22  880 

120 

520 

Black  clay  loam|  87  220 

7 240 

2 680 

61  960 

29  040 

41  760 

40 

528 

Brown  gray 

silt  loam  on  i 

tight  clay 39  720 

3 320 

1 480  | 

71  280 

22  080 

18  360 

440 

Upland  Timber  Soils 


534 

535 
532 

Y ellow-gray  silt 

loam 

Yellow  silt  loam 
Light  gray  silt 
loam  on  tight 
clay 

16  830 
16  900 

20  400 

2 210 
1 870 

1 920 

1 420 
1 610 

1 920 

6 7550 

7 4860 

7 4760 

18  740 
23  140 

23  920 

14  650 
14  340 

17  360 

2 240 
1 300 

720 

Swamp  and  Bottom-Land 

Soils 

1326 

Deep  brown  silt 

loam 

81  370 

6 390 

2 720 

73  ISO 

21  730 

22  470 

90 

1301 

Deep  peat 

511  440 

38  420 

2 480 

3 200 

14  260 

1 362  920 

777  780 

1303 

Shallow  peat 

on  clay 

238  180 

22  180 

4 100 

23  900 

20  740 

j 57  100 

31  140 

'In  2 million  pounds  of  peat  (1301  and  1303). 


Table  U.— Fertility  in  the  Soils  oe  Knox  County 
Average  pounds  per  acre  in  6 million  pounds'  of  subsoil  (about  20  to  40  inches) 


Soil 

Total 

Total 

Total 

Total 

Total 

Total 

Lime- 

Lime 

type 

Soil  type 

organic 

nitro- 

phos- 

potas- 

magne- 

cal- 

stone 

stone 

No. 

carbon 

gen 

phorus 

sium 

sium 

cium 

1 present 

requir'd 

Upland  Prairie  Soils 


526 

Brown  silt  loam 

35  160 

3 630 

2 490 

99  890 

47  110 

35  510 

250 

520 

Black  clay  loam 

25  410 

2 490 

4 050 

100  200 

51  690 

58  290 

19  290 

528 

Brown-gray  silt 

loam  on  tight 

clay 

39  000 

3 300 

2 820 

104  820 

52  980 

32  340 

300 

Upland  Timber  Soils 


534 

535 
532 

Yellow-gray  silt 
loam.. 

Yellow  silt  loam 
Light  gray  silt 
loam  on  tight 
clay 

16  040 

17  570 

28  080 

2 580 
2 150 

2 460 

3 110 

2 780 

3 720 

101  100 
108  580 

112  440 

47  980 
44  440 

48  600 

30  480 
28  940 

34  920 

rarely 

1960 

often 

720 

Swamp  and  Bottom-Land  Soils 

1326 

Deep  brown  silt 

I 

loam 

51  080 

4 180 

3 520 

110  860 

37  740 

29  500 

140 

1301 

Deep  peat  

608  520 

1 45  420 

4 980 

7 470 

j 22  380 

592  020 

1287  750 

1303 

Shallow  peat  on 

clay 

174  420 

| 10  440 

6 720 

93  540 

69  180 

384  540 

724  020 

'In  3 million  pounds  of  deep  peat  (1301). 


Soil  Ricport  No.  6 


[ August , 


INDIVIDUAL,  SOIL  TYPES 

(a)  Upland  Prairie;  Soils 

The  soils  of  this  class  comprise  411.37  square  miles,  or  57  percent  of  the 
entire  county.  They  are  usually  dark  in  color  owing  to  their  large  organic- 
matter  content. 

The  accumulation  of  organic  matter  in  the  prairie  soils  is  due  to  the 
growth  of  prairie  grasses  that  once  covered  them,  and  whose  network  of  roots 
was  protected  from  complete  decay  by  imperfect  aeration  due  to  the  covering 
of  fine  soil  material  and  the  moisture  it  contained.  On  the  native  prairies  the 
tops  of  these  grasses  were  usually  burned  or  became  almost  completely  de- 
cayed. From  a sample  of  virgin  sod  of  “blue  stem,”  one  of  the  most  common 
prairie  grasses,  it  has  been  determined  that  an  acre  of  this  soil  to  a depth  of 
7 inches  contained  13^4  tons  of  roots.  Many  of  these  roots  died  each  year 
and  by  partial  decay  formed  the  humus  of  these  dark  prairie  soils.  In  upland 
forests  no  such  quantity  of  roots  is  found  in  the  soil.  The  vegetable  material 
consists  of  leaves  and  twigs,  which  fall  upon  the  surface  and  either  are  burned 
by  forest  fires  or  undergo  almost  complete  decay.  There  is  very  little  chance 
for  these  to  become  mixed  with  the  soil.  As  a result  the  organic-matter  con- 
tent has  been  lowered  by  the  growth  of  forests  until  in  some  parts  of  the  state 
a low  condition  of  apparent  equilibrium  has  been  reached. 

Broivn  Silt  Loam  (526  or  226) 

This  is  the  most  important  as  well  as  the  most  extensive  type  of  soil  in 
the  county.  It  covers  an  area  of  402.6  square  miles  (257,664  acres),  or  55.87 
percent  of  the  entire  county. 

This  type  is  generally  sufficiently  rolling  for  fair  natural  surface  drain- 
age, altho  tile  drainage  is  often  needed  and  there  are  some  exceptions  where 
the  land  is  so  flat  as  to  require  artificial  surface  drainage.  Some  few  areas 
along  streams  are  so  rolling  that  in  order  to  prevent  washing  they  should  be 
cropped  only  with  the  utmost  care. 

Altho  the  brown  silt  loam  is  normally  a prairie  soil,  in  some  limited 
areas  forests  have  recently  extended  over  the  dark  soil.  These  forests 
consist  quite  largely  of  black  walnut,  with  such  other  trees  as  wild  cherry, 
hackberry,  ash,  hard  maple,  and  elm.  A black-walnut  soil  is  recognized  gen- 
erally by  farmers  as  being  one  of  the  best  timber  soils.  As  a rule  it  still  con- 
tains a large  amount  of  the  organic  matter  that  accumulated  from  the  prairie 
grasses. 

The  surface  soil,  o to  6^3  inches,  is  a brown  silt  loam,  varying  from  it 
yellowish  brown  on  the  more  rolling  areas  to  a dark  brown  or  black  on  the 
more  nearly  level  or  originally  poorly-drained  areas.  The  physical  composi- 
tion varies  to  some  extent,  but  is  normally  a silt  loam  containing  from  70  to 
85  percent  of  the  different  grades  of  silt  together  with  some  sand  and  clay. 
The  amount  of  clay  usually  varies  from  8 to  12  percent;  it  increases  as  the 
type  approaches  the  black  clay  loam  (520)  and  becomes  greatest  in  the  poorly- 
drained  level  areas.  The  amount  of  sand  varies  from  7 to  15  percent  and 
increases  as  the  bottom  land  of  the  large  streams  is  approached. 

The  organic-matter  content  varies  from  3.8  to  7.25  percent  in  the  sur- 
face soil,  or  from  38  to  72.5  tons  per  acre,— about  56  tons  as  an  average. 
Where  this  type  passes  into  the  brown-gray  silt  loam  on  tight  clay  (528)  or 


Knox  County 


23 


1913] 


into  the  yellow-gray  silt  loam  (534),  the  percentage  of  organic  matter  be- 
comes lower,  but  where  it  passes  into  the  black  clay  loam  it  becomes  higher. 

The  natural  subsurface  is  represented  by  a stratum  varying  from  5 to  16 
inches  in  thickness,  being  thinner  on  the  more  rolling  areas  and  thicker  on  the 
level  areas.  Its  physical  composition  varies  in  the  same  way  as  that  of  the 
surface  soil,  but  it  usually  contains  a slightly  larger  amount  of  clay.  Locally 
it  may  become  quite  heavy,  as  where  the  type  grades  into  black  clay  loam.  In 
color  it  varies  from  a dark  brown  or  almost  black  to  a light  brown  or  yellow- 
ish brown,  but  as  a rule  it  becomes  lighter  with  depth  and  passes  gradually 
into  the  yellow  subsoil.  The  color  is  due  to  the  presence  of  organic  matter 
and  to  the  oxidation  of  the  iron.  The  organic-matter  content  averages  3.5 
percent. 

The  natural  subsoil  begins  12  to  23  inches  beneath  the  surface  and  extends 
to  an  indefinite  depth,  but  it  is  usually  sampled  to  40  inches.  It  varies  from 
a yellow  to  a drabbish-yellow  clayey  silt.  In  the  level  or  nearly  level  areas 
it  is  of  a drab  color  mottled  with  yellow  blotches,  while  in  the  more  rolling 
areas  better  drainage  has  allowed  higher  oxidation  of  the  iron  to  take  place, 
giving  the  yellow  to  brownish-yellow  color.  The  upper  8 to  12  inches  of  the 
subsoil  usually  contains  more  clay  than  the  lower  part,  the  coarser  material 
consisting  of  coarse  silt  or  fine  sand.  The  subsoil  contains  about  1 percent 
of  organic  matter,  and  is  generally  pervious  to  water,  permitting  good  under- 
drainage. 

While  most  of  this  type  is  in  fair  physical  condition,  yet  the  continuous 
growing  of  corn,  or  com  and  oats,  with  the  burning  of  the  corn  stalks  and 
possibly  the  oat  stubble  is  reducing  the  organic-matter  content  and  destroying 
the  tilth.  The  soil  is  becoming  more  difficult  to  work ; it  runs  together  more ; 
and  aeration,  granulation,  absorption,  and  moisture  movement  are  interfered 
with. 

This  condition  of  poor  tilth  is  becoming  very  serious  on  many  farms  and 
is  one  of  the  factors  that  limit  crop  yields.  The  remedy  is  to  increase  the 
organic-matter  content  by  plowing  under  crop  residues,  such  as  corn  stalks, 
straw,  clover,  etc.,  instead  of  selling  them  from  the  farm  or  burning  them, 
as  is  often  done  at  present.  The  stalks  should  be  thoroly  cut  up  with  a sharp 
disk  or  stalk  cutter  and  turned  under.  Likewise  the  straw  should  be  put 
back  on  the  land  in  some  practical  way,  either  directly  or  in  the  form  of 
manure.  Clover  should  be  one  of  the  crops  grown  in  the  rotation,  and  it 
should  be  plowed  under  directly  or  as  manure  instead  of  being  sold  as  hay, 
except  where  manure  can  be  brought  back. 

The  addition  of  fresh  organic  matter  is  of  even  greater  importance,  be- 
cause of  its  nitrogen  content  and  because  of  its  power  as  it  decays  to  liberate 
potassium  from  the  inexhaustible  supply  in  the  soil  and  phosphorus  from  the 
phosphate  contained  in  or  applied  to  the  soil. 

For  permanent  profitable  systems  of  farming,  phosphorus  should  be  ap- 
plied liberally,  and  sufficient  organic  matter  should  be  provided  to  furnish 
nitrogen.  On  the  ordinary  brown  silt  loam,  limestone  is  already  becoming 
deficient,  but  this  is  not  always  the  case  on  the  heavier  phase,  which  is  usually 
found  near  draws  or  in  low-lying  areas.  In  live-stock  farming  an  application 
of  two  tons  of  limestone  and  one-half  ton  of  fine-ground  rock  phosphate  per 
acre  every  four  years,  with  the  return  to  the  soil  of  all  manure  made  from  a 
rotation  of  corn,  corn,  oats,  and  clover,  will  maintain  the  fertility  of  this  type, 
altho  heavier  applications  of  phosphate  may  well  be  made  during  the  first 
two  or  three  rotations.  If  grain  farming  is  practiced,  the  rotation  may  be 


24 


Soil  Report  No.  6 


[August, 


wheat,  corn,  oats,  and  clover,  with  an  extra  seeding  of  clover  as  a cover  crop 
in  the  wheat,  to  be  plowed  under  late  in  the  fall  or  the  following  spring  for 
corn ; and  most  of  the  crop  residues,  with  all  the  clover  except  the  seed,  should 
also  be  plowed  under.  In  either  system  alfalfa  may  be  grown  on  a fifth  field 
and  moved  every  five  years,  the  hay  being  fed  or  sold.  (For  results  of  field 
experiments  on  the  brown  silt  loam  prairie,  see  Tables  3 to  9.) 

Black  Clay  Loam  (520) 

This  type  of  soil  represents  the  flat  prairie  (the  naturally  poorly-drained 
areas  of  the  upper  Illinois  glaciation)  and  is  sometimes  called  “gumbo”  be- 
cause of  its  sticky  character.  Its  formation  in  these  places  is  due  to  the 
accumulation  of  organic  matter  and  to  the  washing  in  of  clay  and  fine  silt 
from  the  slightly  higher  adjoining  lands.  This  type  is  not  extensive;  it 
occupies  only  8.31  square  miles  (5,318  acres),  or  1.15  percent  of  the  entire 
area  of  the  county.  In  topography  it  is  so  flat  that  proper  drainage  is  one 
of  the  most  difficult  problems  in  its  management. 

The  surface  stratum  is  a black,  granular  clay  loam  with  7 to  8V2  percent 
of  organic  matter,  or  an  average  of  78  tons  per  acre.  The  wet  condition  of 
the  soil  has  allowed  a greater  accumulation  of  organic  matter  in  this  than  in 
any  other  type  of  upland  soil  in  the  county. 

The  property  of  granulation  is  important  to  all  soils,  but  it  is  especially 
so  to  heavy  ones  or  those  containing  considerable  clay,  since  it  is  by  granula- 
tion that  the  soil  is  kept  mellow  and  rendered  pervious  to  air  and  water.  If 
the  granules  are  destroyed  by  puddling  (as  by  the  tramping  of  stock  while 
the  ground  is  wet),  they  will  be  formed  again  by  freezing  and  thawing  or 
by  wetting  and  drying.  These  natural  agencies  produce  “slacking,”  as  the 
process  is  usually  termed.  If,  however,  the  organic-matter  or  lime  content 
becomes  low,  this  tendency  to  granulate  grows  less  and  the  soil  becomes  more 
difficult  to  work. 

The  subsurface  stratum  extends  to  a depth  of  10  to  16  inches  below  the 
surface  stratum.  It  differs  from  the  surface  in  color,  becoming  lighter  with 
depth,  the  lower  part  of  the  stratum  passing  into  a drab  or  yellowish  silty 
clay,  and  it  also  contains  a higher  percentage  of  clay.  It  is  quite  pervious  to 
water,  due  to  jointing  or  checking  from  shrinkage  in  times  of  drouth.  The 
amount  of  organic  matter  varies  from  3 to  4 percent,  with  an  average  of  3.75 
percent. 

The  subsoil  is  usually  a drab  or  dull  yellow  silty  clay  but  locally  it  may  be 
a yellow  or  clayey  silt.  As  a rule  the  iron  is  not  highly  oxidized  because  of 
poor  drainage  and  lack  of  aeration.  The  subsoil  is  checked  and  jointed, 
making  it  pervious  to  water  and  consequently  easy  to  drain. 

This  type  presents  some  variations.  Here  as  elsewhere  the  boundary  lines 
between  different  soil  types  are  not  always  distinct,  but  types  frequently  pass 
from  one  to  the  other  very  gradually,  thus  giving  an  intermediate  zone  of 
greater  or  less  width.  Gradations  between  brown  silt  loam  (526)  and  black 
clay  loam  (520)  are  very  likely  to  occur  since  they  are  usually  adjoining  types. 
This  gives  a lighter  phase  of  the  black  clay  loam,  with  a smaller  organic- 
matter  content  than  the  average,  and  a heavier  phase  of  the  brown  silt  loam, 
with  a larger  amount  of  organic  matter  than  usual. 

Drainage  is  the  first  requirement  for  this  type,  and  because  of  its  pervious- 
ness it  underdrains  well.  Keeping  the  soil  in  good  physical  condition  is 
very  essential,  and  thoro  drainage  helps  to  do  this  to  a great  extent.  As  the 
organic  matter  is  destroyed  by  cultivation  and  nitrification  and  as  the  lime- 


Knox  County 


25 


1913 ] 


stone  is  removed  by  cropping  and  leaching,  the  physical  condition  of  the  soil 
becomes  poorer,  and  consequently  it  becomes  more  difficult  to  work.  Both  or- 
ganic matter  and  lime  tend  to  develop  granulation.  The  former  should  be 
maintained  by  turning  under  manure,  clover,  and  crop  residues,  such  as  corn- 
stalks and  straw,  instead  of  burning  them  as  is  so  commonly  practiced. 
Ground  limestone  should  be  applied  when  needed  to  keep  the  soil  sweet. 

While  this  type  of  soil  is  one  of  the  best  in  the  state,  yet  the  clay  and 
humus  contained  in  it  give  it  the  property  of  shrinkage  and  expansion  to 
such  a degree  as  to  be  somewhat  objectionable  at  times,  especially  during 
drouth.  When  the  soil  is  wet  these  constituents  expand,  and  when  the  moist- 
ure evaporates  or  is  used  by  crops,  the  soil  shrinks.  The  result  is  the  forma- 
tion of  cracks  up  to  two  inches  or  more  in  width  and  extending  with  lessening 
width  a foot  or  more  in  depth.  These  cracks  permit  the  excessive  loss  of 
moisture  from  the  surface,  subsurface,  and  subsoil.  They  also  sometimes 
“block  out”  the  hills  of  com,  tearing  the  roots  and  doing  considerable  dam- 
age to  the  crop.  While  cracking  may  not  be  prevented  entirely,  yet  good 
tilth  with  a soil  mulch  will  do  much  toward  that  end. 

This  type  is  well  supplied  with  plant  food,  which  is  usually  liberated  with 
sufficient  rapidity  by  a good  rotation  and  the  addition  of  moderate  amounts  of 
organic  matter.  The  amount  of  organic  matter  added  must  be  increased,  of 
course,  with  continued  farming  until  the  nitrogen  supplied  is  equal  to  that  re- 
moved. While  no  marked  profit  is  to  be  expected  from  the  addition  of  phos- 
phorus, it  is  likely  to  pay  its  cost  in  the  second  or  third  rotation,  and  even  by 
maintaining  the  productive  power  of  the  land  the  capital  invested  is  pro- 
tected. This  soil  is  rich  in  magnesium  and  calcium,  and  the  subsoil  usually 
contains  plenty  of  carbonates.  With  continued  cropping  and  leaching,  the  ad- 
dition of  limestone  will  be  necessary.  (No  field  experiments  have  been  con- 
ducted as  yet  on  this  type  of  soil.) 

Broivn-Gray  Silt  Loam  on  Tight  Clay  (528) 

This  type  occupies  only  .46  square  mile  (295  acres),  or  only  .06  percent 
of  the  area  of  the  county.  It  occurs  almost  entirely  in  areas  intermediate 
between  the  prairie  brown  silt  loam  (526)  and  the  timber  yellow-gray  silt 
loam  (5.34).  In  topography  it  is  usually  flat. 

The  surface  soil,  o to  6 2/z  inches,  is  a light  brown  to  a grayish-brown  silt 
loam,  containing  some  fine  sand  and  coarse  silt  that  gives  it  a peculiar  mealy 
“feel.”  The  organic  matter  varies  from  3*4  to  4 percent  according  to  the 
relation  of  this  type  to  other  types,  being  greater  where  it  approaches  brown 
silt  loam  and  less  where  it  passes  into  yellow-gray  silt  loam  (534). 

The  subsurface  is  represented  by  a stratum  of  silt  loam  10  to  12  inches 
thick,  which  varies  in  color  from  brown  to  gray,  usually  from  the  upper  to 
the  lower  parts  of  the  stratum.  It  differs  from  the  surface  in  containing  less 
organic  matter,  the  average  percentage  being  but  1.7. 

The  subsoil  is  a yellowish  clay,  beginning  16  to  18  inches  beneath  the 
surface.  This  clay  stratum  is  not  so  nearly  impervious  as  that  of  the  cor- 
responding type  in  southern  Illinois. 

This  type  should  be  drained  where  necessary.  Care  should  be  taken  to 
increase  the  nitrogen,  and  the  organic-matter  content  by  proper  rotation  and 
by  turning  under  crop  residues,  clover,  or  farm  manure.  Phosphorus  should 
be  used  liberally  in  connection  with  the  decaying  organic  matter,  as  on  the 
brown  silt  loam,  and  limestone  should  also  be  applied  at  the  rate  of  2 to  3 
tons  per  acre  every  four  to  six  years. 


Soil  Report  No.  6 


[August, 


26 


(b)  Upland  Tim3Lr  Soils 
Y elloiv-Gray  Silt  Loam  (534  or  234) 

This  type  occurs  in  the  outer  timber  belts  along  the  streams  and  covers 
104.44  square  miles  (66,842  acres),  or  14^2  percent  of  the  entire  county.  In 
topography  it  is  sufficiently  rolling  for  good  surface  drainage  without  much 
tendency  to  wash  if  proper  care  is  taken. 

The  surface  soil,  o to  6^3  inches,  is  a gray  to  yellowish-gray  silt  loam, 
incoherent  and  mealy,  but  not  granular.  The  amount  of  organic  matter  aver- 
ages about  2.2  percent,  or  22  tons  per  acre. 

The  subsurface  stratum  varies  from'  3 to  10  inches  in  thickness.  The 
greatest  variation  is  due  to  topography,  the  thinner  subsurface  being  on  the 
more  rolling  land.  It  is  a silt  loam,  gray,  grayish-yellow,  or  yellow  in  color, 
somewhat  mealy  but  becoming  more  coherent  and  clayey  with  depth,  and  con- 
taining only  .72  percent  of  organic  matter. 

" The  subsoil  is  a yellow  or  grayish-yellow  mottled  clayey  silt  or  silty  clay, 
somewhat  plastic  when  wet  but  friable  when  moist,  and  pervious  to  water. 

This  type  is  quite  variable  in  texture  because  of  the  fact  that  it  grades 
into  so  many  different  types,  the  transition  zone  between  two  types  showing 
a likeness  to  each. 

Agriculturally,  the  yellow-gray  silt  loam  in  Knox  county  is  second  in  im- 
portance, but  with  the  improvements  easily  possible  its  value  per  acre  may 
become  equal  to  that  of  the  brown  silt  loam.  In  the  management  of  this 
type,  one  of  the  first  essentials  is  the  maintenance  or  increase  of  the  organic 
matter  in  order  to  give  better  tilth,  to  supply  nitrogen  and  liberate  mineral 
plant  food,  to  prevent  running  together,  and  in  some  of  the  more  rolling 
phases  to  prevent  washing.  Another  essential  is  the  application  of  ground 
limestone,  especially  in  order  that  clover,  alfalfa,  and  other  legumes  may  be 
grown  more  successfully.  Liberal  use  should  also  be  made  of  phosphorus, 
since  in  the  surface  stratum  of  this  type  there  is  less  than  900  pounds  to  an 
acre.  (See  Table  2,  page  5.) 

For  definite  results  from  the' most  practical  field  experiments  upon  typical 
yellow-gray  silt  loam,  we  must  go  down  into  “Egypt,”  where  the  people  of 
Saline  county,  especially  those  in  the  vicinity  of  Raleigh  and  Galatia,  have 
provided  the  University  with  a very  suitable  tract  of  this  type  of  soil  for  a 
permanent  experiment  field.  There,  as  an  average  of  triplicate  tests  each  year, 
the  yield  of  corn  on  untreated  land  was  25.3  bushels  in  1910,  23.6  bushels  in 

1911,  and  22  bushels  in  1912;  while  the  corresponding  averages  from  land 
treated  with  heavy  applications  of  limestone  and  a limited  amount  of  organic 
manures  were  41.4  bushels  in  1910,  41.3  bushels  in  1911,  and  50.1  bushels  in 

1912,  the  corn  being  grown  on  a different  series  of  plots  every  year  in  a four- 
year  rotation  of  wheat,  corn,  oats,  and  clover.  About  the  same  proportionate 
increases  were  produced  in  wheat  and  hay,  and  the  effect  on  oats  was  also 
marked. 

Owing  to  the  low  supply  of  organic  matter  and  limestone,  phosphorus 
produced  no  benefit,  as  an  average,  during  the  first  two  years,  but  with  in- 
creasing supplies  of  organic  matter  the  effect  of  phosphorus  is  seen  in  the 
crops  of  1912  and  1913.  Of  course,  a single  four-year  rotation  cannot  be 
practiced  in  less  than  four  years,  and  the  full  benefit  of  the  system  of  rotation 
and  soil  treatment  is  not  to  be  expected  before  .the  third  or  fourth  four-year 
period. 


Knox  County 


1913] 

While  limestone  is  the  material  first  needed  for  the  economic  improve- 
ment of  the  more  acid  soil  of  southern  Illinois,  with  organic  manures  and 
phosphorus  to  follow  in  order,  the  less  acid  soils  of  the  central  and  northern 
parts  of  the  state  are  frequently  most  deficient,  relatively,  in  phosphorus  and 
organic  matter. 

Table  12  shows  in  detail  eleven  years’  results  secured  from  the  Antioch  soil 
experiment  field  located  in  Lake  county  on  the  yellow-gray  silt  loam  of  the 
late  Wisconsin  glaciation.  In  acidity,  this  type  in  Knox  county  is  inter- 
mediate between  the  similar  soils  in  Saline  and  Lake  counties,  but  no  ex- 
periment field  has  been  conducted  on  this  important  soil  type  in  the  upper 
Illinois  glaciation. 

The  Antioch  field  was  started  in  order  to  learn  as  quickly  as  possible  just 
what  effect  would  be  produced  by  the  addition  of  nitrogen,  phosphorus,  and 
potassium,  singly  and  in  combination.  These  elements  have  all  been  added  in 
commercial  form.  Only  a small  amount  of  lime  was  applied  at  the  beginning, 
and  with  the  abnormality  of  Plot  1 and  with  an  abundance  of  limestone  in 
the  subsoil  (a  common  condition  in  the  late  Wisconsin  glaciation),  no  con- 
clusions can  be  drawn  regarding  the  effect  of  lime. 

As  an  average  of  44  tests  (4  each  year  for  11  years),  liberal  applications 
of  commercial  nitrogen  produced  a slight  decrease  in  crop  values,  phosphorus 
paid  back  200  percent  of  its  cost,  while  each  dollar  invested  in  potassium 
brought  back  only  34  cents  (a  net  loss  of  66  percent).  Thus,  while  the 
detailed  data  show  great  variation,  owing  both  to  some  irregularity  of  soil 
and  to  some  very  abnormal  seasons,  with  three  almost  complete  crop  failures 
(1904,  1907,  and  1910),  yet  the  general  summary  strongly  confirms  the 
analytical  data  in  showing  the  need  of  applying  phosphorus  and  the  profit 
from  its  use,  and  the  loss  in  adding  potassium.  In  most  cases  commercial 
nitrogen  damaged  the  small  grains  by  causing  the  crop  to  lodge;  but  when- 
ever a corn  yield  of  40  bushels  or  more  was  secured  where  phosphorus  had 
been  applied  either  alone  or  with  potassium,  then  the  addition  of  nitrogen  pro- 
duced an  increase.  From  a comparison  of  the  results  from  the  Sibley  and 
the  Bloomington  fields,  we  must  conclude  that  better  yields  are  to  be  secured 
by  providing  nitrogen  by  means  of  legume  crops  grown  in  the  rotation  rather 
than  by  the  use  of  commercial  nitrogen,  which  is  evidently  too  readily  avail- 
able. causing  too'  rapid  growth  and  consequent  weakness  of  straw  ; and  of 
course  the  atmosphere  is  the  most  economic  source  of  nitrogen  where  that 
element  is  needed  for  soil  improvement  in  general  farming.  (See  Appendix 
for  detailed  discussion  of  “Permanent  Soil  Improvement.”) 

Yellow  Silt  Loam  (535  or  235) 

This  type  covers  about  133.71  square  miles  (85,574  acres),  or  18.56  percent 
of  the  entire  county.  It  occurs  as  the  hilly  and  badly  eroded  lands  on  the  inner 
timber  belts  along  streams,  usually  only  in  narrow,  irregular  strips  with  arms 
extending  up  the  small  streams.  In  topography  it  is  very  rolling  and  so 
badly  broken  that  as  a rule  it  should  not  be  cultivated  because  of  the  danger 
of  injury  from  washing. 

The  surface  soil,  ‘o  to  6%  inches,  is  a yellow  or  grayish-yellow  mealy 
silt  loam.  It  varies  a great  deal  because  of  recent  washing;  in  some  places 
the  real  subsoil  may  be  exposed.  The  amount  of  organic  matter  varies  from 
1.5  to  3 percent  depending  upon  the  extent  of  the  washing,  but  it  averages 
about  2.2  percent,  or  22  tons  per  acre. 


28 


Soil  Report  No.  6 


[August, 


Table  12. — Crop  Yields  in  Soil  Experiments,  Antioch  Field 


Yellow-gray  silt  loam, 
undulating  timber- 
land;  late  Wisconsin 
glaciation 

Corn 

1902 

Corn 

1903 

Oats 

1904 

Wheat 

1905 

Corn 

1906 

Corn 

1907 

Oats 

1908 

Wheat 

1909 

Corn 

1910 

Corn 

1911 

Oats 

1912 

Plot 

Soil  treatment 
applied 

Bushels  per  acre 

101 

None1 

1 44.8 

36.6 

17.8 

1 18.5 

35.9 

12.4 

I 65.6 

12.2 

I 5.2 

34.4 

21.3 

102 

Lime ... 

45.1 

38.9 

12.8 

10.3 

31.5 

9.5 

| 61.6 

11.7 

3.0 

24.6 

17.5 

103 

Lime,  nitrogen. . . 

46.3 

40.8 

2.8 

17.8 

37.8 

6.4| 

60.3 

13.0 

L4 

10.4 

24.4 

104 

Lime,  phosphorus 

50.1 

53.6 

12.5 

35.8 

57.4 

13.4 

70.9 

23.3 

6.8 

37.4 

49.1 

105 

Lime,  potassium  . 

48.2 

50.2 

9'7| 

21.7 

34.9 

12.9 

62.5 

13.5 

4.6 

20.4 

18.8 

106 

Lime,  nitro.,  phos. 

56.6 

62.7 

1 15.9 

15.2 

59.3 

20.9 

I 49.1 

1 33.8 

6.0 

37.0 

46.9 

107 

Lime,nitro.,potas. 

52.1 

54.9 

10.3 

11.8 

39.0 

11.1 

52.6, 

21.0 

1.6 

7.0 

16.9 

108 

Lime, phos.,  potas. 

60.7 

66.0 

>9.7 

28.7 

59.1 

18.3 

59-4 

26.2 

3.2 

42.2 

35.9 

109 

Lime,  nitro., phos. 
potas 

61.2 

69.1 

31.9 

18.0 

65.9 

31.4 

51.9 

30.5 

3.0 

44.2 

31.9 

110 

Nitro., phos., potas. 

59. 7| 

71.8 

37  * 2| 

16.3 

66.3 

28.8 

55.9 

34.5 

4.0 

49.0 

38.1 

Average  Increase:  Bushels  per  Acre 


For  nitrogen  

3.0 

4.7 

1.6 

-8.4 

4.8 

3.9 

-10.1 

5.9 

-1.4 

-6.5 

-.3 

For  phosphorus 

9.2 

16.7 

11.1 

9.0 

24.6 

11.0 

-1.4 

13.7 

2.1 

24.6 

21.6 

For  potassium 

For  nitro.,  phos.  over 

6.0 

11.0 

6.9 

.3 

3.2 

5.9 

-3.9 

2.3 

-1.2 

1.1 

-8.6 

phos 

For  phos.,  nitro.  over 

6.5 

9.1 

3.4 

-20.6 

1.9 

7.5 

-21.8 

10.5 

-.8 

-.4 

2.2 

nitro 

For  potas.,  nitro.,  phos. 

10.3 

21.9 

13.1 

—2.6 

21.5 

14.5 

-11.2 

20.8 

4.6 

26.6 

22.5 

over  nitro.,  phos 

4.6 

6.4 

16.0 

2.8 

6.6 

10.5 

2.8 

-3.3 

-3.0 

7.2 

-15.0 

Value  of  Crops  per  Acre  in  Eleven  Years 


Plot 

Soil  treatment  applied 

I Total  value 
of  eleven 
crops 

Value  of 
increase 

O O 

None 

$112.16 

96.38 

$-15.78 

103 

104 

105 

Lime,  nitrogen 

Lime,  phosphorus • 

Lime,  potassium 

97.89 

157.67 

111.86 

—14.27 

45.51 

-.30 

106 

107 

108 

Lime,  nitrogen,  phosphorus 

Lime,  nitrogen,  potassium 

Lime,  phosphorus,  potassium  

152.75 

104.89 

160.25 

40.59 

7 27 

48^09 

109 

110 

L,ime  nitrogen,  phosphorus,  potassium. .....  

164.83 

172.78 

52.67 

60.62 

Nitrogen,  phosphorus,  potassium  I 

Value  of  Increase  per  Acre  in  Eleven  Years 

Cost  of 
increase 

For  n 
For  p 
For  n 
For  p 
For  p 

litrogen 

•hosphorus.  ■ 

$1.51 

61.29 

—4.92 

54.86 

12.08 

$165.00 

27.50 

165.00 

27.50 

27.50 

itrogen  and  phosphorus  over  phosphorus 

hosphorus  and  nitrogen  over  nitrogen 

otassium,  nitrogen,  and  phosphorus  over  nitrogen  and 
phosphorus 

’Plot  101,  the  check  plot,  is  the  lowest  ground  but  it  is  well  drained  and  is  appre- 
ciably better  land  than  the  rest  of  the  field.  Plot  102  is  a more  trustworthy  check  plot. 


Knox  County 


29 


1913] 


The  subsurface  varies  from  o to  12  inches  in  thickness  on  account  of  the 
removal  of  part  or  all  of  the  surface  and  subsurface  by  washing. 

The  subsoil  is  a compact  yellow  clayey  silt  which  in  some  places  may  con- 
sist of  glacial  drift  brought  near  the  surface  by  erosion. 

In  the  management  of  this  type,  the  most  important  thing  is  to  prevent 
general  surface  washing  and  gullying.  If  it  is  cropped  at  all,  a rotation  should 
be  practiced  that  will  require  a cultivated  crop  as  little  as  possible  and  allow 
pasture  and  meadow  most  of  the  time.  If  tilled,  the  land  should  be 
plowed  deeply,  and  contours  should  be  followed  as  nearly  as  possibly  both 
in  plowing  and  in  planting.  Furrows  should  not  be  made  extending  up  and 
down  the  slope,  and  the  land  should  be  cultivated  in  the  same  direction  in 
which  it  is  plowed.  Every  means  should  be  employed  to  maintain  and  to  in- 
crease the  organic-matter  content  in  order  to  supply  nitrogen  and  to  help  hold 
the  soil  and  keep  it  in  good  physical  condition  so  that  it  will  absorb  a large 
amount  of  water  and  thus  diminish  the  run-off.  (See  Circular  119.) 

Additional  treatment  recommended  is  the  liberal  use  of  ground  lime- 
stone. This  is  advised  only  where  surface  erosion  has  not  occurred  to  too 
great  an  extent,  and  chiefly  for  such  crops  as  clover  and  alfalfa,  which  can 
often  be  produced  successfully  with  plenty  of  limestone  (5  tons  per  acre), 
thoro  inoculation,  and  about  10  tons  of  farm  manure  to  give  the  young  alfalfa 
a good  start,  after  which  its  extensive  root  system  makes  the  plant  almost 
independent  of  the  surface  soil,  except  for  limestone.  An  initial  application 
of  500  pounds  per  acre  of  steamed  bone  meal  or  acid  phosphate  is  often  help- 
ful in  starting  alfalfa,  especially  where  manure  is  not  available. 


Light  Gray  Silt  Loam  on  Tight  Clay  (532) 

Only  two  very  small  areas  of  this  type,  aggregating  but  12  acres,  are 
shown  on  the  map.  Many  others  occur,  but  they  are  too  small  to  be  repre- 
sented on  a map  of  this  scale. 

The  surface  soil  is  a white  or  light  gray  silt  loam,  incoherent,  mealy,  and 
porous.  Spherical  iron  concretions  are  usually  present.  The  organic-matter 
content  is  low,  amounting  to  only  about  2.2  percent,  or  22  tons  per  acre. 

The  subsurface  is  a light  gray  silt  extending  to  a depth  of  14  to  18  inches, 
becoming  more  clayey  with  depth  and  containing  only  .7  percent  of  organic 
matter. 

The  subsoil  is  a tight,  compact,  plastic,  clayey  silt,  yellow  with  gray  mot- 
tlings. 

Besides  being  deficient  in  organic  matter,  this  type  is  lacking  in  limestone 
and  is  consequently  in  poor  physical  condition.  It  runs  together  badly  and, 
owing  to  the  strong  capillarity  in  the  surface  and  subsurface  strata,  it  does 
not  hold  moisture  well.  In  the  management  of  this  soil,  ground  limestone 
should  be  used  liberally,  rock  phosphate  should  be  added,  and  the  organic- 
matter  content  increased  in  every  practical  way.  Deep-rooting  crops,  such 
as  red,  mammoth,  or  sweet  clover,  would  loosen  the  tight  clay  subsoil  as  well 
as  supply  the  soil  with  organic  matter  and  nitrogen.  Crop  residues  or  farm 
manure  should  be  plowed  under  to  bring  the  soil  into  better  tilth. 


30 


Soil  Report  No.  6 


[August, 


(c)  Swamp  and  Bottom-Land  Soils 
Deep  Brown  Silt  Loam  (1326) 

The  bottom-land  soil  is  derived  from  material  washed  from  the  upland, 
and  must  therefore  have  some  relation  to  the  upland  soils.  It  differs  in  being 
more  variable  in  physical  composition  than  any  single  upland  type,  and  the 
brown  color  extends  into  it  to  greater  depth.  The  bottoms  along  the  streams 
of  the  county  vaty  from  a few  rods  to  a mile  or  more  in  width.  These  lands 
occupy  71.09  square  miles  (45,498  acres),  and  constitute  9.86  percent  of  the 
entire  area  of  the  county.  In  topography  they^are  flat  or  have  very  slight 
undulations  that  represent  old  stream  or  overflow  channels.  Better  drainage 
is  needed  in  much  of  this  area. 

The  surface  soil,  o to  6^3  inches,  is  usually  a brown  silt  loam  contain- 
ing from  3.5  to'  5.3  percent  of  organic  matter,  the  average  being  4.4  percent, 
or  44  tons  per  acre.  Tt  is  probably  easier  to  maintain  the  fertility  and  the 
organic  matter  in  this  type  than  in  the  upland  types,  because  of  occasional 
overflow  and  the  consequent  deposition  of  material  rich  in  humus  and  plant 
food.  In  physical  composition  this  soil  varies  from  a clay  loam  to  a sandy 
loam,  but  the  areas  of  these  extreme  types,  especially  of  the  sandy  loam,  are 
so  small  and  so  changeable  that  it  is  impracticable  to  try  to  show  them  on  the 
map,  as  the  next  flood  may  change  their  boundaries. 

The  subsurface  is  brown  silt  loam,  becoming  lighter  in  color  and  fre- 
quently in  texture  with  depths  It  contains  an  average  of  3.2  percent  6f  or- 
ganic matter. 

The  subsoil  is  a yellowish-drab  silt  loam  varying  in  physical  composition 
either  to  a clayey  silt  or  to  a sandy  loam,  or  even  to  a sand  in  the  lower  sub- 
soil. Because  of  the  way  in  which  this  type  was  formed,  the  different  strata 
necessarily  vary  greatly. 

Where  proper  drainage  is  secured  the  type  is  quite  productive.  As  a rule, 
where  it  is  subject  to  frequent  overflow  nothing  is  needed  except  good  farm- 
ing. Even  the  systematic  rotation  of  crops  is  not  so  important  where  the 
land  is  subject  to  occasional  overflows,  but  where  it  lies  high  or  is  protected 
from  overflow  a rotation  including  legume  crops  should  be  practiced,  and  ul- 
timately provision  should  be  made  for  the  enrichment  of  such  protected  land 
in  both  phosphorus  and  organic  matter,  and  if  necessary  in  limestone. 

Deep  Peat  (1301) 

A small  area  of  deep  peat,  covering  about  26  acres,  is  found  in  Section  1, 
Township  9 North,  Range  3 East.  This  area  needs  drainage  first  of  all.  The 
surface  soil,  o to  6^3  inches,  is  a brown  somewhat  marly  peat,  varying  in 
composition  because  of  silts  carried  in  and  deposited  by  water.  Both  sub- 
surface and  subsoil  are  brown  peat  mixed  with  shells. 

The  samples  collected  and  analyzed  show  great  deficiency  in  potassium 
and  only  moderate  amounts  of  phosphorus.  The  addition  of  100  to  200 
pounds  per  acre  of  potassium  chlorid  (often  erroneously  called  “muriate”  of 
potash)  is  almost  certain  to  produce  very  marked  benefit;  and  where  this  is 
done,  phosphorus  is  likely  to  prove  profitable  in  the  future.  When  manure 
is  applied,  it  will  furnish  potassium  and  produce  increased  crops,  as  a rule, 
but  if  the  supply  of  manure  is  limited,  it  may  be  a better  plan  to  use  it  on  other 


Knox  County 


31 


79/5] 

land,  and  improve  this  with  commercial  materials.  (See  also  Bulletin  157, 
“Peaty  Swamp  Lands;  Sand  and  ‘Alkali’  Soils.”) 

Shallozu  Peat  on  Clay  (1303) 

This  type  occupies  an  area  of  about  19  acres  in  the  southwest  quarter  of 
Section  7,  Township  9 North,  Range  3 East,  on  the  edge  of  the  bottom  land. 
It  includes  some  medium  peat,  but  shallow  peat  predominates. 

The  surface  soil,  o to  6 ^ inches,  is  a brown  peat  containing  some  shells. 
The  subsurface  consists  of  a stratum  of  brown  peat  varying  from  4 to  10 
inches  in  thickness  underlain  by  a drab  clay  that  constitutes  the  subsoil. 

Aside  from  drainage,  very  deep  plowing,  which  will  mix  some  of  the 
clay  with  the  peaty  stratum,  is  the  only  special  treatment  recommended. 
(See  Bulletin  157  for  results  of  such  plowing  on  similar  land.) 


32 


Soil  Report  No.  6 


[August, 


APPENDIX 

A study  of  the  soil  map  and  the  tabular  statements  concerning  crop  re- 
quirements, the  plant-food  content  of  the  different  soil  types,  and  the  actual 
results  secured  from  definite  field  trials  with  different  methods  or  systems 
of  soil  improvement,  and  a careful  study  of  the  discussion  of  general  prin- 
ciples and  of  the  descriptions  of  individual  soil  types,  will  furnish  the  most 
necessary  and  useful  information  for  the  practical  improvement  and  perma- 
nent preservation  of  the  productive  power  of  every  kind  of  soil  on  every 
farm  in  the  county. 

More  complete  information  concerning  the  most  extensive  and  impor- 
tant soil  types  in  the  great  soil  areas  in  all  parts  of  Illinois  is  contained  in 
Bulletin  123,  “The  Fertility  in  Illinois  Soils,”  which  contains  a colored  gen- 
eral survey  soil  map  of  the  entire  state. 

Other  publications  of  general  interest  are : 

Bulletin  No.  76,  “Alfalfa  on  Illinois  Soils” 

Bulletin  No.  94;  “Nitrogen  Bacteria  and  Legumes” 

Bulletin  No.  115,  “Soil  Improvement  for  the  Worn  Hill  Lands  of  Illinois” 

Bulletin  No.  125,  “Thirty  Years  of  Crop  Rotation  on  the  Common  Prairie  Lands  of 
Illinois” 

Circular  No.  no,  “Ground  Limestone  for  Acid  Soils” 

Circular  No.  127,  “Shall  we  use  Natural  Rock  Phosphate  or  Manufactured  Acid  Phos- 
phate for  the  Permanent  Improvement  of  Illinois  Soils?” 

Circular  No.  129,  “The  Use  of  Commercial  Fertilizers” 

Circular  No.  149,  “Some  Results  of  Scientific  Soil  Treatment”  and  “Methods  and  Re- 
sults of  Ten  Years’  Soil  Investigation  in  Illinois” 

Circular  No.  165,  “Shall  we  use  ‘Complete’  Commercial  Fertilizers  in  the  Corn  Belt?” 

NOTE. — Information  as  to  where  to  obtain  limestone,  phosphate,  bone  meal,  and  po- 
tassium salts,  methods  of  application,  etc.,  will  also  be  found  in  Circulars  no  and  165. 

Soil  Survey  Methods 

The  detail  soil  survey  of  a county  consists  essentially  of  indicating  on 
a map  the  location  and  extent  of  the  different  soil  types;  and,  since  the 
value  of  the  survey  depends  upon  its  accuracy,  every  reasonable  means  is 
employed  to  make  it  trustworthy.  To  accomplish  this  object  three  things 
are  essential : first,  careful,  well-trained  men  to  do  the  work ; second,  an  ac- 
curate base  map  upon  which  to  show  the  results  of  their  work:  and,  third, 
the  means  necessary  to  enable  the  men  to  place  the  soil-type  boundaries, 
streams,  etc.,  accurately  upon  the  map. 

The  men  selected  for  the  work  must  be  able  to  keep  their  location 
exactly  and  to  recognize  the  different  soil  types,  with  their  principal  varia- 
tions and  limits,  and  they  must  show  these  upon  the  maps  correctly.  A 
definite  system  is  employed  in  checking  up  this  work.  As  an  illustration,  one 
soil  expert  will  survey  and  map  a strip  80  rods  or  160  rods  wide  and  any 
convenient  length,  while  his  associate  will  work  independently  on  another 
strip  adjoining  this  area,  and,  if  the  work  is  correctly  done,  the  soil  type 
boundaries  will  match  up  on  the  line  between  the  two  strips. 

An  accurate  base  map  for  field  use  is  absolutely  necessary  for  soil  map- 
ping. The  base  maps  are  made  on  a scale  of  one  inch  to  the  mile.  The 
official  data  of  the  original  or  subsequent  land  survey  are  used  as  a basis  in 
the  construction  of  these  maps,  while  the  most  trustworthy  county  map  avail- 
able is  used  in  locating  temporarily  the  streams,  roads,  and  railroads,  Since 
the  best  of  these  published  maps  have  some  inaccuracies,  the  location  of  every 
road,  stream,  and  railroad  must  be  verified  by  the  soil  surveyors,  and  cor- 


I9I3\ 


Knox  County 


33 


rectecl  if  wrongly  located.  In  order  to  make  these  verifications  and  correc- 
tions, each  survey  party  is  provided  with  an  odometer  for  measuring  dis- 
tances, and  a plane  table  for  determining  directions  of  roads,  railroads,  etc. 

Each  surveyor  is  provided  with  a base  map  of  the  proper  scale,  which  is 
carried  with  him  in  the  field;  and  the  soil-type  boundaries,  additional  streams, 
and  necessary  corrections  are  placed  in  their  proper  locations  upon  the  map 
while  the  mapper  is  on  the  area.  Each  section,  or  square  mile,  is  divided  into 
40-acre  plots  on  the  map,  and  the  surveyor  must  inspect  every  ten  acres  and 
determine  the  type  or  types  of  soil  composing  it.  The  different  types  are 
indicated  on  the  map  by  different  colors,  pencils  for  this  purpose  being  car- 
ried in  the  field. 

A small  auger  40  inches  long  forms  for  each  man  an  invaluable  tool  with 
which  he  can  quickly  secure  samples  of  the  different  strata  for  inspection. 
An  extension  for  making  the  auger  80  inches  long  is  taken  by  each  party, 
so  that  any  peculiarity  of  the  deeper  subsoil  layers  may  be  studied.  Each 
man  carries  a compass  to  aid  in  keeping  directions.  Distances  along  roads 
are  measured  by  an  odometer  attached  to  the  axle  of  the  vehicle,  while  dis- 
tances in  the  field  off  the  roads  are  determined  by  pacing,  an  art  in  which 
the  men  become  expert  by  practice.  The  soil  boundaries  can  thus  be  located 
with  as  high  a degree  of  accuracy  as  can  be  indicated  by  pencil  on  the 
scale  of  one  inch  to  the  mile. 


The  unit  in  the  soil  survey  is  the  soil  type,  and  each  type  possesses  more 
or  less  definite  characteristics.  The  line  of  separation  between  adjoining 
types  is  usually  distinct,  but  sometimes  one  type  grades  into  another  so 
gradually  that  it  is  very  difficult  to  draw  the  line  between  them.  In  such 
exceptional  cases,  some  slight  variation  in  the  location  of  soil-type  boundaries 
is  unavoidable. 

Several  factors  must  be  taken  into  account  in  establishing  soil  types. 
These  are  (1)  the  geological  origin  of  the  soil,  whether  residual,  glacial, 
loessial,  alluvial,  colluvial,  or  cumulose;  (2)  the  topography,  or  lay  of  the 
land;  (3)  the  native  vegetation,  as  forest  or  prairie  grasses;  (4)  the  structure, 
or  the  depth  and  character  of  the  surface,  subsurface,  and  subsoil;  (5)  the 
physical, or  mechanical, composition  of  the  different  strata  composing  the  soil, 
as  the  percentages- of  gravel,  sand,  silt,  clay,  and  organic  matter  which  they 
contain;  (6)  the  texture,  or  porosity,  granulation,  friability,  plasticity,  etc.; 
(7)  the  color  of  the  strata;  (8)  the  natural  drainage;  (9)  agricultural 
value,  based  upon  its  natural  productiveness;  (10)  the  ultimate  chemical 
composition  and  reaction. 

The  common  soil  constituents  are  indicated  in  the  following  outline : 


Son,  Characteristics 


Constituents  of  Soils 


Organic 

Matter 


J Comprising  1 
1 vegetable 


undecomposed  and  partially  decayed 
: material 


Soil 

Constituents 


.001  mm.1  and  less 
001  mm.  to  .03  mm. 
. .03  mm.  to  1.  mm. 

, . .1.  mm.  to  32  mm. 
...32.  mm.  and  over 


Inorganic 

Matter 


125  millimeters  equal  1 inch. 

Further  discussion  of  these  constituents  is  given  in  Circular  82. 


Soil  Report  No.  6 


[August, 


34 


Groups  of  Soil  Typfs 

The  following  gives  the  different  general  groups  of  soils: 

Peats — Consisting  of  35  percent  or  more  of  organic  matter,  sometimes 
mixed  with  more  or  less  sand  or  silt. 

Peaty  loams — 15  to  35  percent  of  organic  matter  mixed  with  much  sand 
and  silt  and  a little  clay. 

Mucks — 15  to  35  percent  of  partly  decomposed  organic  matter  mixed 
with  much  clay  and  some  silt. 

Clays — Soils  with  more  than  25  percent  of  clay,  usually  mixed  with  much 
silt. 

Clay  loams — Soils  with  from  15  to  25  percent  of  clay,  usually  mixed 
with  much  silt  and  some  sand. 

Silt  loams — Soils  with  more  than  50  percent  of  silt  and  less  than  15 
percent  of  clay,  mixed  with  some  sand. 

Loams — Soils  with  from  30  to  50  percent  of  sand  mixed  with  much  silt 
and  a little  clay. 

Sandy  loams— Soils  with  from  50  to  75  percent  of  sand. 

Fine  sandy  loams — Soils  with  from  50  to  75  percent  of  fine  sand  mixed 
with  much  silt  and  little  clay. 

Sands — Soils  with  more  than  75  percent  of  sand. 

Gravelly  loams — Soils  with  15  to  50  percent  of  gravel  with  much  sand 
and  some  silt. 

Gravels — Soils  with  more  than  50  percent  of  gravel. 

Stony  loams — Soils  containing  a considerable  number  of  stones  over  one 
inch  in  diameter. 

Rock  outcrop — Usually  ledges  of  rock  having  no  agricultural  value. 

More  or  less  organic  matter  is  found  in  nearly  all  the  above  classes. 

Supply  and  Liberation  of  Plant  Food 

The  productive  capacity  of  land  in  humid  sections  depends  almost  wholly 
upon  the  power  of  the  soil  to  feed  the  crop ; and  this,  in  turn,  depends  both 
upon  the  stock  of  plant  food  contained  in  the  soil  and  upon  the  rate  at  which 
this  is  liberated,  or  rendered  soluble  and  available  for  use  in  plant  growth. 
Protection  from  weeds,  insects,  and  fungous  diseases,  tho  exceedingly  im- 
portant, is  not  a positive  but  a negative  factor  in  crop  production. 

The  chemical  analysis  of  the  soil  gives  the  invoice  of  fertility  actually 
present  in  the  soil  strata  sampled  and  analyzed,  but  the  rate  of  liberation  is 
governed  by  many  factors,  some  of  which  may  be  controlled  by  the  farmer, 
while  others  are  largely  beyond  his  control.  Chief  among  the  important 
controllable  factors  which  influence  the  liberation  of  plant  food  are  lime- 
stone and  decaying  organic  matter,  which  may  be  added  to  the  soil  by  direct 
application  of  ground  limestone  and  farm  manure.  Organic  matter  may  be 
supplied  also  by  green-manure  crops  and  crop  residues,  such  as  clover,  cow- 
peas,  straw,  and  cornstalks.  The  rate  of  decay  of  organic  matter  depends 
largely  upon  its  age  and  origin,  and  it  may  be  hastened  by  tillage.  The 
chemical  analysis  shows  correctly  the  total  organic  carbon,  which  represents, 
as  a rule,  but  little  more  than  half  the  organic  matter;  so  that  20,000 
pounds  of  organic  carbon  in  the  plowed  soil  of  an  acre  correspond  to  nearly 


Knox  County 


35 


20  tons  of  organic  matter.  But  this  organic  matter  consists  largely  of  the 
old  organic  residues  that  have  accumulated  during  the  past  centuries  because 
they  were  resistant  to  decay,  and  2 tons  of  clover  or  cowpeas  plowed  under 
may  have  greater  power  to  liberate  plant  food  than  the  20tons  of  old,  inactive 
organic  matter.  The  recent  history  of  the  individual  farm  or  field  must  be 
depended  upon  for  information  concerning  recent  additions  of  active  organic 
matter,  whether  in  applications  of  farm  manure,  in  legume  crops,  or  in  grass- 
root  sods  of  old  pastures. 

Probably  no  agricultural  fact  is  more  generally  known  by  farmers  and 
landowners  than  that  soils  differ  in  productive  power.  Even  tho  plowed 
alike  and  at  the  same  time,  prepared  the  same  way,  planted  the  same  day 
with  the  same  kind  of  seed,  and  cultivated  alike,  watered  by  the  same  rains 
and  warmed  by  the  same  sun,  nevertheless  the  best  acre  may  produce  twice 
as  large  a crop  as  the  poorest  acre  on  the  same  farm,  if  not,  indeed,  in  the 
same  field;  and  the  fact  should  be  repeated  and  emphasized  that  with  the 
normal  rainfall  of  Illinois  the  productive  power  of  the  land  depends  primarily 
upon  the  stock  of  plant  food  contained  in  the  soil  and  upon  the  rate  at  which 
it  is  liberated,  just  as  the  success  of  the  merchant  depends  primarily  upon 
his  stock  of  goods  and  the  rapidity  of  sales.  In  both  cases  the  stock  of  any 
commodity  must  be  increased  or  renewed  whenever  the  supply  of  such  com- 
modity becomes  so  depleted  as  to  limit  the  success  of  the  business,  whether 
on  the  farm  or  in  the  store. 

As  the  organic  matter  decays,  certain  decomposition  products  are  formed, 
including  much  carbonic  acid,  some  nitric  acid,  and  various  organic  acids, 
and  these  have  power  to  act  upon  the  soil  and  dissolve  the  essential  mineral 
plant  foods,  thus  furnishing  soluble  phosphates,  nitrates,  and  other  salts  "of 
potassium,  magnesium,  calcium,  etc.,  for  the  use  of  the  growing  crop. 

'As  already  explained,  fresh  organic  matter  decomposes  much  more  rap- 
idly than  the  old  humus,  which  represents  the  organic  residues  most  resistant 
to  decay  and  which  consequently  has  accumulated  in  the  soil  during  the 
past  centuries.  The  decay  of  this  old  humus  can  be  hastened  both  by  tillage, 
which  maintains  a porous  condition  and  thus  permits  the  oxygen  of  the  air 
to  enter  the  soil  more  freely  and  to  effect  the  more  rapid  oxidation  of  the 
organic  matter,  and  also  by  incorporating  with  the  old,  resistant  residues 
some  fresh  organic  matter,  such  as  farm  manure,  clover  roots,  etc.,  which 
decay  rapidly  and  thus  furnish  or  liberate  organic  matter  and  inorganic  food 
for  bacteria,  the  bacteria,  under  such  favorable  conditions,  appearing  to  have 
power  to  attack  and  decompose  the  old  humus.  It  is  probably  for  this  reason 
that  peat,  a very  inactive  and  inefficient  fertilizer  when  used  by  itself,  becomes 
much  more  effective  when  incorporated  with  fresh  farm  manure;  so  that, 
when  used  together,  two  tons  of  the  mixture  may  be  worth  as  much  as  two 
tons  of  manure,  but  if  applied  separately,  the  peat  has  little  value.  Bacterial 
action  is  also  promoted  by  the  presence  of  limestone. 

' The  condition  of  the  organic  matter  of  the  soil  is  indicated  more  or  less 
definitely  by  the  ratio  of  carbon  to  nitrogen.  As  an  average,  the  fresh 
organic  matter  incorporated  with  soils  contains  about  twenty  times  as  much 
carbon  as  nitrogen,  but  the  carbohydrates  ferment  and  decompose  much  more 
rapidly  than  the  nitrogenous  matter;  and  the  old  resistant  organic  residues, 
such  as  are  found  in  normal  subsoils,  commonly  contain  only  five  or  six  times 
as  much  carbon  as  nitrogen.  Soils  of  normal  physical  composition,  such 
as  loam,  clay  loam,  silt  loam,  and  fine  sandy  loam,  when  in  good  productive 


Soil  Report  No.  6 


[August, 


36 


condition,  contain  about  twelve  to  fourteen  times  as  much  carbon  as  nitrogen 
in  the  surface  soil ; while  in  old,  worn  soils  that  are  greatly  in  need  of  fresh, 
active,  organic  manures,  the  ratio  is  narrower,  sometimes  falling  below  ten  of 
carbon  to  one  of  nitrogen.  (Except  in  newly  made  alluvial  soils,  the  ratio 
is  usually  narrower  in  the  subsurface  and  subsoil  than  in  the  surface  stratum.) 

It  should  be  kept  in  mind  that  crops  are  not  made  out  of  nothing.  They 
are  composed  of  ten  different  elements  of  plant  food,  every  one  of  which  is 
absolutely  essential  for  the  growth  and  formation  of  every  agricultural  plant. 
Of  these  ten  elements  of  plant  food,  only  two  (carbon  and  oxygen)  are 
secured  from  the  air  by  all  agricultural  plants,  only  one  (hydrogen)  from 
water,  and  seven  from  the  soil.  Nitrogen,  one  of  these  seven  elements 
secured  from  the  soil  by  all  plants,  may  also  be  secured  from  the  air  by  one 
class  of  plants  (legumes),  in  case  the  amount  liberated  from  the  soil  is  insuf- 
ficient; but  even  these  plants  (which  include  only  the  clovers,  peas,  beans,  and 
vetches,  among  our  common  agricultural  plants)  secure  from  the  soil  alone 
six  elements  (phosphorus,  potassium,  magnesium,  calcium,  iron  and  sulfur), 
and  also  utilize  the  soil  nitrogen  so  far  as  it  becomes  soluble  and  available 
during  their  period  of  growth. 

Plants  are  made  of  plant-food  elements  in  just  the  same  sense  that 
a building  is  made  of  wood  and  iron,  brick,  stone,  and  mortar.  Without 
materials,  nothing  material  can  be  made.  The  normal  temperature,  sunshine, 
rainfall,  and  length  of  season  in  central  Illinois  are  sufficient  to  produce 
50  bushels  of  wheat  per  acre,  100  bushels  of  corn,  100  bushels  of  oats,  and 
4 tons  of  clover  hay;  and,  where  the  land  is  properly  drained  and  properly 
tilled,  such  crops  would  frequently  be  secured  if  the  plant  foods  were  present 
in  sufficient  amounts  and  liberated  at  a sufficiently  rapid  rate  to  meet  the  abso- 
lute needs  of  the  crops. 

Crop  Requirements 

The  accompanying  table  shows  the  requirements  of  such  crops  for  the 
five  most  important  plant-food  elements  which  the  soil  must  furnish.  (Iron 
and  sulfur  are  supplied  normally  in  sufficient  abundance  compared  with  the 
amounts  needed  by  plants,  so  that  they  are  not  known  ever  to  limit  the  yield 
of  general  farm  crops  grown  under  normal  conditions.) 


Table  A. — Plant  Food  in  Wheat,  Corn,  Oats,  and  Clover 


Produce 

Nitro- 

gen, 

pounds 

Phos- 

phorus, 

pounds 

Potas- 

sium, 

pounds 

Magne- 

sium, 

pounds 

Cal- 

cium, 

pounds 

Kind 

Amount 

Wheat,  grain 

50  bu. 

71 

12 

13 

4 

1 

Wheat  straw 

2 l/z  tons 

25 

4 

45 

4 

10 

Corn,  grain 

100  bu. 

100 

17 

19 

7 

1 

Corn  stover 

3 tons 

48 

6 

52 

10 

21 

Corn  cobs  

K ton 

2 

2 

Oats,  grain 

100  bu. 

66 

11 

16 

4 

2 

Oat  straw  

2 tons 

31 

5 

52 

7 

15 

Clover  seed 

4 bu. 

7 

2 

3 

1 

1 

Clover  hay. . 

4 tons 

160 

20 

120 

31 

117 

Total  in  grain  and  Seed 

2441 

42 

51 

16 

4 

Total  in  four  crops 

5101 

77 

322 

68 

168 

lThese  amounts  include  the  nitrogen  contained  in  the  clover  seed  or  hay,  which, 
however,  may  be  secured  from  the  air. 


1913 ] 


Knox  County 


37 


To  be  sure,  these  are  large  yields,  but  shall  we  try  to  make  possible  the 
production  of  yields  only  half  or  a quarter  as  large  as  these,  or  shall  we 
set  as  our  ideal  this  higher  mark,  and  then  approach  it  as  nearly  as  possible 
with  profit?  Among  the  four  crops,  corn  is  the  largest,  with  a total  yield 
of  more  than  six  tons  per  acre;  and  yet  the  ioo-bushel  crop  of  corn  is  often 
produced  on  rich  pieces  of  land  in  good  seasons.  In  very  practical  and 
profitable  systems  of  farming,  the  Illinois  Experiment  Station  has  produced, 
as  an  average  of  the  six  years  1905  to  1910,  a yield  of  87  bushels  of  corn 
per  acre  in  grain  farming  (with  limestone  and  phosphorus  applied,  and  with 
crop  residues  and  legume  crops  turned  under),  and  90  bushels  per  acre  in 
live-stock  farming  (with  limestone,  phosphorus,  and  manure). 

^ The  importance  of  maintaining  a rich  surface  soil  cannot  be  too  strongly 
emphasized.  This  is  well  illustrated  by  data  from  the  Rothamsted  Experi- 
ment Station,  the  oldest  in  the  world.  Thus  on  Broadbalk  field,  where  wheat 
has  been  grown  since  1844,  the  average  yields  for  the  ten  years  1892  to  1901 
were  12.3  bushels  per  acre  on  Plot  3 (unfertilized)  and  31.8  bushels  on 
Plot  7 (well  fertilized),  but  the  amounts  of  both  nitrogen  and  phosphorus 
in  the  subsoil  (9  to  27  inches)  were  distinctly  greater  in  Plot  3 than  in 
Plot  7,  thus  showing  that  the  higher  yields  from  Plot  7 were  due  to  the 
fact  that  the  plowed  soil  had  been  enriched.  In  1893  Plot  7 contained  per 
acre  in  the  surface  soil  (o  to  9 inches)  about  600  pounds  more  nitrogen  and 
900  pounds  more  phosphorus  than  Rot  3.  Even  a rich  subsoil  has  little 
value  if  it  lies  beneath  a worn-out  surface. 

Methods  of  Liberating  Plant  Food 

Limestone  and  decaying  organic  matter  are  the  principal  materials  the 
farmer  can  utilize  most  profitably  to  bring  about  the  liberation  of  plant  food. 

The  limestone  corrects  the  acidity  of  the  soil  and  thus  encourages  the 
development  not  only  of  the  nitrogen-gathering  bacteria  which  live  in  the 
nodules  on  the  roots  of  clover,  cowpeas,  and  other  legumes,  but  also  the 
nitrifying  bacteria,  which  have  power  to  transform  the  insoluble  and  unavail- 
able organic  nitrogen  into  soluble  and  available  nitrate  nitrogen. 

At  the  same  time,  the  products  of  this  decomposition  have  power  to  dis- 
solve the  minerals  contained  in  the  soil,  such  as  potassium  and  magnesium, 
and  also  to  dissolve  the  insoluble  phosphate  and  limestone  which  may  be 
applied  in  low-priced  forms. 

Tillage,  or  cultivation,  also  hastens  the  liberation  of  plant  food  by  permit- 
ting the  air  to  enter  the  soil  and  burn  out  the  organic  matter;  but  it  should 
never  be  forgotten  that  tillage  is  wholly  destructive,  that  it  adds  nothing 
whatever  to  the  soil,  but  always  leaves  the  soil  poorer.  Tillage  should  be 
practiced  so  far  as  is  necessary  to  prepare  a suitable  seed-bed  for  root  devel- 
opment and  also  for  the  purpose  of  killing  weeds*  but  more  than  this  is 
unnecessary  and  unprofitable  in  seasons  of  normal  rainfall;  and  it  is  much 
better  actually  to  enrich  the  soil  by  proper  applications  or  additions,  including 
limestone  and  organic  matter  (both  of  which  have  power  to  improve  the 
physical  condition  as  well  as  to  liberate  plant  food)  than  merely  to  hasten 
soil  depletion  by  means  of  excessive  cultivation. 

Permanent  Soil  Improvement 

The  best  and  most  profitable  methods  for  the  permanent  improvement  of 
the  common  soils  of  Illinois  are  as  follows : 


38 


Soil  Report  No.  6 


[ August , 


(i)  If  the  soil  is  acid,  apply  at  least  two  tons  per  acre  of  ground  lime- 
stone, preferably  at  times  magnesian  limestone  (CaC03MgC03),  which 
contains  both  calcium  and  magnesium  and  has  slightly  greater  power  to  cor- 
rect soil  acidity,  ton  for  ton,  than  the  ordinary  calcium  limestone  (CaC03)  ; 
and  continue  to  apply  about  two  tons  per  acre  of  ground  limestone  every  four 
or  five  years.  On  strongly  acid  soils,  or  in  preparing  the  land  for  alfalfa,  five 
tons  per  acre  of  ground  limestone  may  well  be  used  for  the  first  application. 

(2)  Adopt  a good  rotation  of  crops,  including  a liberal  use  of  legumes, 
and  increase  the  organic  matter  of  the  soil  either  by  plowing  under  the 
legume  crops  and  other  crop  residues  (straw  and  corn  stalks),  or  by  using 
for  feed  and  bedding  practically  all  the  crops  raised  and  returning  the 
manure  to  the  land  with  the  least  possible  loss.  No  one  can  say  in  advance 
what  will  prove  to  be  the  best  rotation  of  crops,  because  of  variation  in 
farms  and  farmers,  and  in  prices  for  produce,  but  the  following  are  suggested 
to  serve  as  models  or  outlines : 

First  year,  corn. 

Second  year,  corn. 

Third  year,  wheat  or  oats  (with  clover  or  clover  and  grass). 

Fourth  year,  clover  or  clover  and  grass. 

Fifth  year,  wheat  and  clover  or  grass  and  clover. 

Sixth  year,  clover  or  clover  and  grass. 

Of  course  there  should  be  as  many  fields  as  there  are  years  in  the  rota- 
tion. In  grain  farming,  with  small  grain  grown  the  third  and  fifth  years,  most 
of  the  coarse  products  should  be  returned  to  the  soil,  and  the  clover  may  be 
clipped  and  left  on  the  land  (only  the  clover  seed  being  sold  the  fourth  and 
sixth  years)  ; or,  in  live-stock  farming,  the  field  may  be  used  three  years  for 
timothy  and  clover  pasture  and  meadow  if  desired.  The  system  may  be 
reduced  to  a five-year  rotation  by  cutting  out  either  the  second  or  the  sixth 
year,  and  to  a four-year  system  by  omitting  the  fifth  and  sixth  years. 

With  two  years  of  corn,  followed  by  oats  with  clover-seeding  the  third 
year,  and  by  clover  the  fourth  year,  all  produce  can  be  used  for  feed  and 
bedding  if  other  land  is  available  for  permanent  pasture.  Alfalfa  may  be 
grown  on  a fifth  field  for  four  or  eight  years,  which  is  to  be  alternated  with 
one  of  the  four;  or  the  alfalfa  may  be  moved  every  five  years,  and  thus 
rotated  over  all  five  fields  every  twenty-five  years. 

Other  four-year  rotations  more  suitable  for  grain  farming  are : 

Wheat  (and  clover),  corn,  oats,  and  clover;  or  corn  (and  clover),  cowpeas,  wheat, 
and  clover.  (Alfalfa  may  be  grown  on  a fifth  field  and  rotated  every  five  years, 
the  hay  being  sold.) 

Good  three-year  rotations  are : 

Corn,  oats,  and  clover;  corn,  wheat,  and  clover;  or  wheat  (and  clover),  corn  (and 
clover),  and  cowpeas,  in  which  two  cover  crops  and  one  regular  crop  of  legumes 
are  grown  in  three  years. 

A five-year  rotation  of  (1)  corn  (and  clover),  (2)  cowpeas,  (3)  wheat, 
(4)  clover,  and  (5)  wheat  (and  clover)  allows  legumes  to  be  seeded  four 
times,  and  alfalfa  may  be  grown  on  a sixth  field  for  five  or  six  years  in  the 
combination  rotation,  alternating  between  two  fields  every  five  years,  or 
rotating  over  all  the  fields  if  moved  every  six  years. 

To  avoid  clover  sickness  it  may  sometimes  be  necessary  to  substitute  sweet 
clover  or  alsike  for  red  clover  in  about  every  third  rotation,  and  at  the  same 


Knox  County 


39 


1913] 

time  to  discontinue  its  use  in  the  cover-crop  mixture.  If  the  corn  crop 
is  not  too  rank,  cowpeas  or  soybeans  may  also  be  used  as  a cover  crop  (seeded 
at  the  last  cultivation)  in  the  southern  part  of  the  state,  and,  if  necessary 
to  avoid  disease,  these  may  well  alternate  in  successive  rotations. 

For  easy  figuring  it  may  well  be  kept  in  mind  that  the  following  amounts 
of  nitrogen  are  required  for  the  produce  named : 

1 bushel  of  oats  (grain  and  straw)  requires  1 pound  of  nitrogen. 

1 bushel  of  corn  (grain  and  stalks)  requires  V/2  pounds  of  nitrogen. 

1 bushel  of  wheat  (grain  and  straw)  requires  2 pounds  of  nitrogen. 

I ton  of  timothy  requires  24  pounds  of  nitrogen. 

I ton  of  clover  contains  40  pounds  of  nitrogen. 

1 ton  of  cowpeas  contains  43  pounds  of  nitrogen. 

I ton  of  average  manure  contains  10  pounds  of  nitrogen. 

The  roots  of  clover  contain  about  half  as  much  nitrogen  as  the  tops,  and 
the  roots  of  cowpeas  contain  about  one-tenth  as  much  as  the  tops. 

Soils  of  moderate  productive  power  will  furnish  as  much  nitrogen  to 
clover  (and  two  or  three  times  as  much  to  cowpeas)  as  will  be  left  in  the 
roots  and  stubble.  For  grain  crops,  such  as  wheat,  corn,  and  oats,  about  two- 
thirds  of  the  nitrogen  is  contained  in  the  grain  and  one-third  in  the  straw 
or  stalks.  (See  also  discussion  of  “The  Potassium  Problem,”  on  pages  below.) 

(3)  On  all  lands  deficient  in  phosphorus  (except  on  those  susceptible 
to  serious  erosion  by  surface  washing  or  gullying)  apply  that  element  in 
considerably  larger  amounts  than  are  required  to  meet  the  actual  needs  of 
the  crops  desired  to  be  produced.  The  abundant  information  thus  far  se- 
cured shows  positively  that  fine-ground  natural  rock  phosphate  can  be  used 
successfully  and  very  profitably,  and  clearly  indicates  that  this  material  will 
be  the  most  economical  form  of  phosphorus  to  use  in  all  ordinary  systems 
of  permanent,  profitable  soil  improvement.  The  first  application  may  well 
be  one  ton  per  acre,  and  subsequently  about  one-half  ton  per  acre  every  four 
or  five  years  should  be  applied,  at  least  until  the  phosphorus  content  of  the 
plowed  soil  reaches  2,000  pounds  per  acre,  which  may  require  a total  ap- 
plication of  from  three  to  five  or  six  tons  per  acre  of  raw  phosphate  con- 
taining \2]/2  percent  of  the  element  phosphorus. 

Steamed  bone  meal  and  even  acid  phosphate  may  be  used  in  emergencies, 
but  it  should  always  be  kept  in  mind  that  phosphorus  delivered  in  Illinois 
costs  about  3 cents  a pound  in  raw  phosphate  (direct  from  the  mine  in  car- 
load lots),  but  10  cents  a pound  in  steamed  bone  meal,  and  about  12  cents 
a pound  in  acid  phosphate,  both  of  which  cost  too  much  per  ton  to  permit 
their  common  purchase  by  farmers  in  carload  lots,  which  is  not  the  case 
with  limestone  or  raw  phosphate. 

Phosphorus  once  applied  to  the  soil  remains  in  it  until  removed  in  crops, 
unless  carried  away  mechanically  by  soil  erosion.  (The  loss  by  leaching 
is  only  about  il/2  pounds  per  acre  per  annum,  so  that  more  than  150  years 
would  be  required  to  leach  away  the  phosphorus  applied  in  one  ton  of  raw 
phosphate.) 

The  phosphate  and  limestone  may  be  applied  at  any  time  during  the 
rotation,,  but  a good  method  is  to  apply  the  limestone  after  plowing  and 
work  it  into  the  surface  soil  in  preparing  the  seed  bed  for  wheat,  oats,  rye, 
or  barley,  where  clover  is  to  be  seeded;  while  phosphate  is  best  plowed  under 
with  farm  manure,  clover,  or  other  green  manures,  which  serve  to  liberate 
the  phosphorus. 


40 


Soil  Report  No.  6 


[August, 


(4)  Until  the  supply  of  decaying  organic  matter  has  been  made  ade- 
quate, on  the  poorer  types  of  upland  timber  and  gray  prairie  soils  some 
temporary  benefit  may  be  derived  from  the  use  of  a soluble  salt  or  mixture 
of  salts,  such  as  kainit,  which  contains  both  potassium  and  magnesium  in 
soluble  form  and  also  some  common  salt  (sodium  chlorid) . About  600 
pounds  per  acre  of  kainit  applied  and  turned  under  with  the  raw  phosphate 
will  help  to  dissolve  the  phosphorus  as  well  as  to  furnish  available  potas- 
sium and  magnesium,  and  for  a few  years  such  use  of  kainit  will  no  doubt 
be  profitable  on  lands  deficient  in  organic  matter,  but  the  evidence  thus  far 
secured  indicates  that  its  use  is  not  absolutely  necessary  and  that  it  will  not 
be  profitable  after  adequate  provision  is  made  for  decaying  organic  matter, 
since  this  will  necessitate  returning  to  the  soil  either  all  produce  except  the 
grain  (in  grain  farming)  or  the  manure  produced  in  live-stock  farming. 
(Where  hay  or  straw  is  sold,  manure  should  be  bought.) 

On  soils  which  are  subject  to  surface  washing,  including  especially  the 
yellow  silt  loam  of  the  upland  timber  area,  and  to  some  extent  tne  yeiiow- 
gray  silt  loam,  and  other  more  rolling  areas,  the  supply  of  minerals  in  the 
subsurface  and  subsoil  (which  gradually  renew  the  surface  soil)  tends  to 
provide  for  a low-grade  system  of  permanent  agriculture  if  some  use  is  made 
of  legume  plants,  as  in  long  rotations  with  much  pasture,  because  both  the 
minerals  and  nitrogen  are  thus  provided  in  some  amount  almost  permanently ; 
but  where  such  lands  are  farmed  under  such  a system,  not  more  than  two  or 
three  grain  crops  should  be  grown  during  a period  of  ten  or  twelve  years, 
the  land  being  kept  in  pasture  most  of  the  time ; and  where  the  soil  is  acid  a 
liberal  use  of  limestone,  as  top-dressings  if  necessary,  and  occasional  re- 
seeding with  clovers  will  benefit  both  the  pasture  and  indirectly  the  grain 
crops. 

Advantage  oe  Crop  Rotation  and  Permanent  Systems 

It  should  be  noted  that  clover  is  not  likely  to  be  well  infected  with  the 
clover  bacteria  during  the  first  rotation  on  a given  farm  or  field  where  it 
has  not  been  grown  before  within  recent  years;  but  even  a partial  stand  of 
clover  the  first  time  will  probably  provide  a thousand  times  as  many  bac- 
teria for  the  next  clover  crop  as  one  could  afford  to  apply  in  artificial  inocu- 
lation, for  a single  root-tubercle  may  contain  a million  bacteria  developed 
from  one  during  the  season’s  growth. 

This  is  only  one  of  several  advantages  of  the  second  course  of  the  rota- 
tion over  the  first  course.  Thus  the  mere  practice  of  crop  rotation  is  an  ad- 
vantage, especially  in  helping  to  rid  the  land  of  insects  and  foul  grass  and 
weeds.  The  deep-rooting  clover  crop  is  an  advantage  to  subsequent  crops 
because  of  that  characteristic.  The  larger  applications  of  organic  manures 
(made  possible  by  the  larger  crops)  are  a great  advantage;  and  in  systems 
of  permanent  soil  improvement,  such  as  are  here  advised  and  illustrated, 
more  limestone  and  more  phosphorus  are  provided  than  are  needed  for  the 
meager  or  moderate  crops  produced  during  the  first  rotation,  and  conse- 
quently the  crops  in  the  second  rotation  have  the  advantage  of  such  accumu- 
lated residues  (well  incorporated  with  the  plowed  soil)  in  addition  to  the 
regular  applications  made  during  the  second  rotation.  v 

This  means  that  these  systems  tend  positively  toward  the  making  of 
richer  lands.  The  ultimate  analyses  recorded  in  the  tables  give  the  absolute 
invoice  of  these  Illinois  soils.  They  show  that  most  of  them  are  positively 
deficient  only  in  limestone,  phosphorus,  and  nitrogenous  organic  matter:  and 


1913 1 


Knox  County 


41 


the  accumulated  information  from  careful  and  long-continued  investigations 
in  different  parts  of  the  United  States  clearly  establishes  the  fact  that  in  gen- 
eral farming  these  essentials  can  be  supplied  with  greatest  economy  and 
profit  by  the  use  of  ground  natural  limestone,  very  finely  ground  natural 
rock  phosphate,  and  legume  crops  to  be  plowed  under  directly  or  in  farm 
manure.  On  normal  soils  no  other  applications  are  absolutely  necessary, 
but,  as  already  explained,  the  addition  of  some  soluble  salt  in  the  beginning 
of  a system  of  improvement  on  some  of  these  soils  produces  temporary 
benefit,  and  if  some  inexpensive  salt,  such  as  kainit,  is  used,  it  may  produce 
sufficient  increase  to  more  than  pay  the  added  cost. 

The  Potassium  Problem 

As  reported  in  Illinois  Bulletin  123,  where  wheat  has  been  grown  every 
year  for  more  than  half  a century  at  Rothamsted,  England,  exactly  the  same 
increase  was  produced  (5.6  bushels  per  acre),  as  an  average  of  the  first 
24  years,  whether  potassium,  magnesium,  or  sodium  was  applied,  the  rate  of 
application  per  annum  being  200  pounds  of  potassium  sulfate  and  molecular 
equivalents  of  magnesium  sulfate  and  sodium  sulfate.  As  an  average  of 
60  years  (1852  to  1911),  the  yield  of  wheat  has  been  12.7  bushels  on  un- 
treated land,  23.3  bushels  where  86  pounds  of  nitrogen  and  29  pounds  of 
phosphorus  per  acre  per  annum  were  applied;  and,  as  further  additions,  85 
pounds  of  potassium  raised  the  yield  to  31.3  bushels;  52  pounds  of  mag- 
nesium raised  it  to  29.2  bushels;  and  50  pounds  of  sodium  raised  it  to 
29.5  bushels.  Where  potassium  was  applied,  the  average  wheat  crop  re- 
moved 40  pounds  of  that  element  in  the  grain  and  straw,  or  three  times  as 
much  as  would  be  removed  in  the  grain  only  for  such  crops  as  are  suggested 
in  Table  A.  The  Rothamsted  soil  contained  an  abundance  of  limestone,  but  no 
organic  matter  was  provided  except  the  little  in  the  stubble  and  roots  of  the 
wheat  plants. 

On  another  field  at  Rothamsted  the  average  yield  of  barley  for  60  years 
(1852  to  1911)  has  been  14.2  bushels  on  untreated  land,  38.1  bushels  where 
43  pounds  of  nitrogen  and  29  pounds  of  phosphorus  have  been  applied 
per  acre  per  annum;  while  the  further  addition  of  85  pounds  of  potassium, 
19  pounds  of  magnesium,  and  14  pounds  of  sodium  (all  in  sulfates)  raised 
the  average  yield  to  41.5  bushels,  but,  where  only  70  pounds  of  sodium  were 
applied  in  addition  to  the  nitrogen  and  phosphorus,  the  average  has  been 
43.0  bushels.  Thus,  as  an  average  of  60  years,  the  use  of  sodium  pro- 
duced 1.8  bushels  less  wheat  and  1.5  bushels  more  barley  than  the  use  of 
potassium,  with  both  grain  and  straw  removed  and  no  organic  manures 
returned. 

In  recent  years  the  effect  of  potassium  is  becoming  much  more  marked 
than  that  of  sodium  or  magnesium,  on  the  wheat  crop;  but  this  must  be 
expected  to  occur  in  time  where  no  potassium  is  returned  in  straw  or  manure, 
and  no  provision  made  for  liberating  potassium  from  the  supply  still  re- 
maining in  the  soil.  If  more  than  three-fourths  of  the  potassium  removed 
were  returned  in  the  straw  (see  Table  A),  and  if  the  decomposition  prod- 
ucts of  the  straw  have  power  to  liberate  additional  amounts  of  potassium 
from  the  soil,  the  necessity  of  purchasing  potassium  in  a good  system  of 
farming  on  such  land  is  very  remote. 

While  about  half  the  potassium,  nitrogen,  and  organic  matter,  and 
about  one-fourth  the  phosphorus  contained  in  manure  will  be  lost  by 
three  or  four  months’  exposure  in  the  ordinary  pile  in  the  barn  yard,  there 


42 


Soil  Report  No.  6 


[August. 


is  practically  no  loss  if  plenty  of  absorbent  bedding  is  used  on  cement  floors, 
and  if  the  manure  is  hauled  to  the  field  and  spread  within  a day  or  two 
after  it  is  produced.  Again,  while  the  animals  destroy  two-thirds  of  the 
organic  matter  and  retain  one-fourth  of  the  nitrogen  and  phosphorus  in 
average  live-stock  farming,  they  retain  less  than  one-tenth  of  the  potassium, 
from  the  food  consumed ; so  that  the  actual  loss  of  potassium  in  the  products 
sold  from  the  farm,  either  in  grain  farming  or  in  live-stock  farming,  is 
wholly  negligible  on  land  containing  25,000  pounds  or  more  of  potassium 
in  the  surface  67^  inches. 

The  removal  of  one  inch  of  soil  per  century  by  surface  washing  (which 
is  likely  to  occur  wherever  there  is  satisfactory  surface  drainage  and  frequent 
cultivation)  would  permanently  maintain  the  potassium  in  grain  farming 
by  renewal  from  the  subsoil,  provided  one-third  of  the  potassium  is  removed 
by  cropping  before  the  soil  is  carried  away. 

From  all  of  these  facts  it  will  be  seen  that  the  potassium  problem  is  not 
one  of  addition  but  of  liberation;  and  the  Rothamsted  records  show  that 
for  many  years  other  soluble  salts  have  practically  the  same  power  as  po- 
tassium to  increase  crop  yields  in  the  absence  of  sufficient  decaying  organic 
matter.  Whether  this  action  relates  to  supplying  or  liberating  potassium  for 
its  own  sake,  or  to  the  power  of  the  soluble  salt  to  increase  the  availability 
of  phosphorus  or  other  elements,  is  not  known,  but  where  much  potassium 
is  removed,  as  in  the  entire  crops  at  Rothamsted,  with  no  return  of  organic 
residues,  probably  the  soluble  salt  functions  in  both  ways. 

As  an  average  of  112  separate  tests  conducted  in  1907,  1908,  1909,  and 
1910  on  the  Fairfield  experiment  field,  an  application  of  200  pounds  of 
potassium  sulfate,  containing  85  pounds  of  potassium  and  costing  $5.10,  in- 
creased the  yield  of  corn  by  9.3  bushels  per  acre:  while  600  pounds  of  kainit, 
containing  only  60  pounds  of  potassium  and  costing  $4.00,  gave  an  increase 
of  10.7  bushels.  Thus,  at  40  cents  a bushel  for  corn,  the  kainit  has  paid  for 
itself;  but  these  results,  like  those  at  Rothamsted,  were  secured  where  no 
adequate  provision  had  been  made  for  decaying  organic  matter. 

Additional  experiments  at  Fairfield  include  an  equally  complete  test  with 
potassium  sulfate  and  kainit  on  land  to  which  8 tons  per  acre  of  farm 
manure  had  been  applied.  As  an  average  of  112  tests  with  each  material, 
the  200  pounds  of  potassium  sulfate  increased  the  yield  of  corn  by  1.7  bush- 
els, while  the  600  pounds  of  kainit  also  gave  an  increase  of  1.7  bushels. 
Thus,  where  organic  manure  was  supplied,  very  little  effect  was  produced 
by  the  addition  of  either  potassium  sulfate  or  kainit;  in  part  perhaps  because 
the  potassium  removed  in  the  crops  is  mostly  returned  in  the  manure  if 
properly  cared  for,  and  perhaps  in  larger  part  because  the  decaying  organic 
matter  helps  to  liberate  and  hold  in  solution  other  plant-food  elements,  es- 
pecially phosphorus . 

In  laboratory  experiments  at  the  Illinois  Experiment  Station,  it  has  been 
shown  that  potassium  salts  and  most  other  soluble  salts  increase  the  solu- 
bility of  the  phosphorus  in  soil  and  in  rock  phosphate  as  determined  by  chem- 
ical analysis;  also  that  the  addition  of  glucose  with  rock  phosphate  in  pot- 
culture  experiments  increases  the  availability  of  the  phosphorus,  as  measured 
by  plant  growth,  altho  the  glucose  consists  only  of  carbon,  hydrogen,  and 
oxygen,  and  thus  contains  no  plant  food  of  value. 

If  we  remember  that,  as  an  average,  live  stock  destroy  two-thirds  of  the 
organic  matter  of  the  food  consumed,  it  is  easy  to  determine  from  Table  A 


Knox  County 


I9i3\ 

that  more  organic  matter  will  be  supplied  in  a proper  grain  system  than 
in  a strictly  live-stock  system;  and  the  evidence  thus  far  secured  from  older 
experiments  at  the  University  and  at  other  places  in  the  state  indicates  that 
if  the  corn  stalks,  straw,  clover,  etc.,  are  incorporated  with  the  soil  as  soon 
as  practicable  after  they  are  produced  (which  can  usually  be  done  in  the 
late  fall  or  early  spring),  there  is  little  or  no  difficulty  in  securing  sufficient 
decomposition  in  our  humid  climate  to  avoid  serious  interference  with  the 
capillary  movement  of  the  soil  moisture,  a common  danger  from  plowing'  un- 
der too  much  coarse  manure  of  any  kind  in  the  late  spring  of  a dry  year. 

If,  however,  the  entire  produce  of  the  land  is  sold  from  the  farm,  as 
in  hay  farming,  or  when  both  grain  and  straw  are  sold,  of  course  the  draft 
on  potassium  will  then  be  so  great  that  in  time  it  must  be  renewed  by  some 
sort  of  application.  As  a rule,  such  farmers  ought  to  secure  manure  from 
town,  since  they  furnish  the  bulk  of  the  material  out  of  which  manure  is 
produced. 

Calcium  and  Magnesium 

When  measured  by  the  actual  crop  requirements  for  plant  food,  mag- 
nesium and  calcium  are  more  limited  in  some  Illinois  soils  than  potassium. 
But  with  these  elements  we  must  also  consider  the  loss  by  leaching.  As  an 
average  of  90  analyses1  of  Illinois  well-waters  drawn  chiefly  from  glacial 
sands,  gravels,  or  till,  3 million  pounds  of  water  (about  the  average  annual 
drainage  per  acre  for  Illinois)  contained  11  pounds  of  potassium,  130  of 
magnesium,  and  330  of  calcium.  These  figures  are  very  significant,  and  it 
may  be  stated  that  if  the  plowed  soil  is  well  supplied  with  the  carbonates  of 
magnesium  and  calcium,  then  a very  considerable  proportion  of  these 
amounts  will  be  leached  from  that  stratum.  Thus  the  loss  of  calcium  from 
the  plowed  soil  of  an  acre  at  Rothamsted,  England,  where  the  soil  contains 
plenty  of  limestone,  has  averaged  more  than  300  pounds  a year  as  determined 
by  analyzing  the  soil  in  1865  and  again  in  T905'.  And  practically  the  same 
amount  of  calcium  was  found  by  analyzing  the  Rothamsted  drainage  waters. 

Common  limestone,  which  is  calcium  carbonate  (CaC03),  contains,  when 
pure,  40  percent  of  calcium,  so  that  800  pounds  of  limestone  are  equivalent 
to  320  pounds  of  calcium.  Where  10  tons  per  acre  of  ground  limestone  were 
applied  at  Edgewood,  Illinois,  the  average  annual  loss  during  the  next  ten 
years  amounted  to  790  pounds  per  acre.  The  definite  data  from  careful 
investigations  seem  to  be  ample  to  justify  the  conclusion  that  where  lime- 
stone is  needed  at  least  2 tons  per  acre  should  be  applied  every  4 or  5 years. 

It  is  of  interest  to  note  that  thirty  crops  of  clover  of  four  tons  each 
would  require  3,510  pounds  of  calcium,  while  the  most  common  prairie  land 
of  southern  Illinois  contains  only  3,420  pounds  of  total  calcium  in  the 
plowed  soil  of  an  acre.  ("See  Soil  Report  No.  1.)  Thus  limestone  has  a 
positive  value  on  some  soils  for  the  plant  food  which  it  supplies,  in  addition 
to  its  value  in  correcting  soil  acidity  and  in  improving  the  physical  condi- 
tion of  the  soil.  Ordinary  limestone  (abundant  in  the  southern  and  western 
parts  of  the  state)  contains  nearly  800  pounds  of  calcium  per  ton;  while  a 
good  grade  of  dolomitic  limestone  (the  more  common  limestone  of  northern 
Illinois)  contains  about  400  pounds  of  calcium  and  300  pounds  of  mag- 
nesium per  ton.  Both  of  these  elements  are  furnished  in  readily  available 
form  in  ground  dolomitic  limestone. 


1Reported  by  Doctor  Bartow  and  associates,  of  the  Illinois  State  Water  Survey. 


UNIVERSITY  OF  ILLINOIS 


Agricultural  Experiment  Station 


SOIL  REPORT  NO.  7 


McDonough  county  soils 


By  CYRIE  G.  HOPKINS,  J.  G.  MOSIER, 
J.  H.  PETTIT,  and  O.  S.  FISHER 


URBANA,  ILLINOIS,  SEPTEMBER,  1913 


State  Advisory  Committee  on-  Soil  Investigations 
Ralph  Allen,  Delavan  A.  N.  Abbott,  Morrison 

F.  I.  Mann,  Gilman.  J.  P.  Mason,  Elgin 

C.  V.  Gregory,  538  S.  Clark  Street,  Chicago 

Agricultural  Experiment  Station  Staff  on  Soil  Investigations 
Eugene  Davenport,  Director 

Cyril  G.  Hopkins,  Chief  in  Agronomy  and  Chemistry 


Soil  Survey — 

J.  G.  Mosier,  Chief 
A.  F.  Gustafson,  Associate 
S.  V.  Holt,  Associate 
H.  W.  Stewart,  Associate 
H.  C.  Wheeler,  Associate 
F.  A.  Fisher,  Assistant 

F.  M.  W.  Wascher,  Assistant 
R.  W.  Dickenson,  Assistant 

G.  E.  Gentle,  Assistant 
O.  I.  Ellis,  Assistant 


Soil  Experiment  Fields — 

O.  S.  Fisher,  Assistant  Chief 
J.  E.  Whitchurch,  Associate 

E.  E.  Hoskins,  Associate 

F.  C.  Bauer,  Associate 
F.  W.  Garrett,  Assistant 
H.  C.  Gilkerson,  Assistant 

H.  F.  T.  Fahrnkopf,  Assistant 
A.  F.  Heck,  Assistant 
H.  J.  Snider,  Assistant 


Soil  Analysis — 

J.  H.  Pettit,  Chief  Soil  Biology — 

E.  Van  Alstine,  Associate  a.  L.  Whiting,  Associate 

J P.  Aumer,  Associate  W.  R Schoonover,  Assistant 

W.  H.  Sachs,  Associate 
Gertrude  Niederman,  Assistant 
W.  R.  Leighty,  Assistant 

L.  R.  Binding,  Assistant  Soils  Extension — 

C.  B.  Clevenger,  Assistant  C.  C.  Logan,  Associate 


introductory  note 

About  two-thirds  of  Illinois  lies  in  the  corn  belt,  where  most  of  the 
prairie  lands  are  black  or  dark  brown  in  color.  In  the  southern  third  of  the 
state,  the  prairie  soils  are  largely  of  a gray  color.  This  region  is  better 
known  as  the  wheat  belt,  altho  wheat  is  often  grown  in  the  corn  belt  and 
corn  is  also  a common  crop  in  the  wheat  belt. 

Moultrie  county,  representing  the  corn  belt ; Clay  county,  which  is  fairly 
repVesentative  of  the  wheat  belt ; and  Hardin  county,  which  is  taken  to  rep- 
resent the  unglaciated  area  of  the  extreme  southern  part  of  the  state,  were 
selected  for  the  first  Illinois  Soil  Reports  by  counties.  While  these  three 
county  soil  reports  were  sent  to  the  Station’s  entire  mailing  list  within  the 
state,  subsequent  reports  are  sent  only  to  the  residents  of  the  county  con- 
cerned, and  to  any  one  else  upon  request. 

Each  county  report  is  intended  to  be  as  nearly  complete  in  itself  as  it 
is  practicable  to  make  it,  and,  even  at  the  expense  of  some  repetition,  each 
will  contain  a general  discussion  of  important  fundamental  principles  in  order 
to  help  the  farmer  and  landowner  understand  the  meaning  of  the  soil  fer- 
tility invoice  for  the  lands  in  which  he  is  interested.  In  Soil  Report  No.  1, 
“Clay  County  Soils,”  this  discussion  serves  in  part  as  an  introduction,  while 
in  this  and  other  reports,  it  will  be  found  in  the  Appendix;  but  if  necessary 
it  should  be  read  and  studied  in  advance  of  the  report  proper. 


McDonough  county  soils 

By  CYRIL  G.  HOPKINS,  J.  G.  MOSIER,  J.  H.  PETTIT,  and  O.  S.  FISHER 


McDonough  county  is  located  in  the  upper  Illinois  glaciation  about  mid- 
way between  the  Illinois  and  Mississippi  rivers.  It  is  divided  into  two  rather 
distinct  topographic  areas : the  southwestern,  consisting  largely  of  rolling  or 
broken  land,  with  good  drainage;  and  the  northern  and  eastern,  of  gently 
undulating  topography  and  containing  several  areas  originally  very  poorly 
drained.  The  rolling  or  hilly  land  comprizes  25  percent  of  the  entire  area  of 
the  county. 

The  difference  in  topography  is  due  mainly  to  stream  erosion,  but  it  is 
very  probable  that  an  ice  sheet  which  once  covered  the  county  did  a great 
deal  toward  producing  the  present  topography,  especially  in  the  region  where 
erosion  has  played  only  a small  part.  The  time  when  this  county  and  much 
of  the  state  was  covered  with  this  ice  shqet  is  known  as  the  Glacial  period. 
During  that  period  accumulations  of  snow  and  ice  in  parts  of  Canada  became 
so  great  that  they  pushed  southward  until  a point  was  reached  where  the 
ice  melted  as  rapidly  as  it  advanced.  In  moving  across  the  country,  the  ice 
gathered  up  all  sorts  and  sizes  of  stone  and  earth  materials,  including  masses 
of  rock,  boulders,  pebbles,  and  smaller  particles.  Some  of  these  materials 
were  carried  for  hundreds  of  miles  and  rubbed  against  the  surface  rocks  or 
against  each  other  until  ground  into  powder.  When  the  limit  of  advance 
was  reached,  where  the  ice  largely  melted,  this  material  would  accumulate  in 
a broad  undulating  ridge  or  moraine.  When  the  ice  melted  away  more  rap- 
idly than  the  glacier  advanced,  the  terminus  of  the  glacier  would  recede  and 
leave  the  moraine  of  glacial  drift  to  mark  the  outer  limit  of  the  ice  sheet. 

The  ice  made  many  advances  and  with  each  advance  and  recession  a 
terminal  moraine  was  formed.  These  moraines  are  now  seen  as  broad  ridges 
that  vary  from  one  to  ten  miles  in  width.  McDonough  county  possesses  no 
distinct  morainal  ridge.  Thruout  the  state,  however,  these  advances  and  re- 
cessions of  the  ice  sheet  left  a system  of  terminal  moraines  (irregularly  con- 
centric with  Lake  Michigan)  having  generally  a steep  outer  slope  while  the 
inner  slope  is  longer  and  more  gradual.  (See  state  map  in  Bulletin  123.) 

The  material  transported  by  the  glacier  varied  with  the  character  of  the 
rocks  over  which  it  passed.  Granites,  limestones,  sandstones,  shales,  etc., 
were  mixed  and  ground  up  together.  This  mixture  of  all  kinds  of  boulders, 
gravel,  sand,  silt,  and  clay  is  called  boulder  clay,  till,  glacial  drift,  or  simply 
drift.  The  grinding  and  denuding  power  of  glaciers  is  enormous.  A mass 
of  ice  100  feet  thick  exerts  a pressure  of  40  pounds  per  square  inch,  and  this 
ice  sheet  may  have  been  thousands  of  feet  in  thickness.  The  materials  car- 
ried and  pushed  along  in  this  mass  of  ice,  especially  the  boulders  and  pebbles, 
became  powerful  agents  for  grinding  and  wearing  away  the  surface  over 
which  the  ice  passed.  Ridges  and  hills  were  rubbed  down,  valleys  filled,  and 
surface  features  changed  entirely. 


2 


Soil  Repoet  No.  7 


[September, 


As  the  glacier  melted  in  its  final  recession,  the  material  carried  in  the 
great  mass  of  ice  was  deposited  somewhat  uniformly,  yet  not  entirely  so, 
over  the  intermorainal  tracts,  leaving  extensive  areas  of  level,  undulating,  or 
rolling  plains.  Practically  the  whole  of  McDonough  county  is  covered  with 
a deposit  of  this  glacial  drift,  or  boulder  clay,  to  a depth  varying  from  io 
to  140  feet  and  averaging  approximately  50  to  60  feet.  An  illustration  of 
an  old  filled  valley  is  found  in  Macomb.  According  to  Leverett,  a deep  well 
in  the  city  penetrates  145  feet  of  drift,  while  other  wells  in  the  vicinity,  at 
the  same  altitude,  show  only  60  feet  of  drift.  This  indicates  a buried  valley 
that  was  at  least  85  feet  deep.  The  surface  left  by  the  glacier  in  this  county 
was  slightly  rolling,  but  not  sufficiently  so  for  complete  drainage. 

Physiography 

McDonough  county  lies  entirely  in  the  drainage  basin  of  the  Illinois 
river.  The  highest  part  of  the  county  is  the  northwest,  where  an  altitude  of 
775  feet  above  sea  level  is  reached.  The  lowest  part  is  in  the  bottom  land 
of  Crooked  creek  at  the  south  side  of  the  county,  which  lies  at  an  altitude  of 
500  feet.  The  average  altitude  is  approximately  690  feet.  Following  are 
the  altitudes  of  some  of  the  railroad  stations:  Adair,  645;  Bardolph,  671; 
Blandinsville,  730;  Bushnell,  658;  Colchester,  694;  Good  Hope,  714;  Ma- 
comb, 700;  New  Philadelphia,  673;  Prairie  City,  659;  Sciota,  754;  Ten- 
nessee, 686. 

At  least  90  percent  of  McDonough  county  is  drained  thru  Crooked  creek ; 
the  other  10  percent  is  drained  eastward  into  Spoon  river.  The  larger 
streams  of  the  county  have  cut  valleys  from  50  to  200  feet  below  the  general 
upland.  This  has  permitted  the  small  tributaries  to  do  considerable  erosion, 
and  as  a result  the  upland  adjacent  to  these  larger  streams  is  largely  cut  up 
into  hills  and  valleys  unsuited  for  ordinary  agriculture. 

Soil  Material  and  Soil  Types 

The  Illinois  glacier  covered  McDonough  county  and  left  a thick  mantle 
of  drift,  completely  burying  the  old  soil  that  preceded  it.  Then  a long 
period  elapsed  during  which  a deep  soil,  known  as  the  old  Sangamon  soil, 
was  formed  on  the  Illinois  drift.  Later,  other  ice  invasions  of  Illinois  oc- 
curred, but  they  covered  only  the  northern  part  of  the  state.  (See  state  map 
in  Bulletin  123,  Iowan  and  Wisconsin  glaciations.) 

These  later  ice  sheets  did  not  reach  McDonough  county,  but  finely  ground 
rock  (rock  flour)  in  immense  quantities  was  carried  south  by  the  waters  from 
the  melting  ice  and  deposited  on  the  flooded  plains  of  streams  where  it  was 
picked  up  by  the  wind,  carried  out  of  these  bottom  lands  and  finally  deposited 
on  the  upland,  burying  the  drift  material  deposited  by  the  Illinois  glacier  and 
the  old  Sangamon  soil1  to  a depth  of  5 to  20  feet  or  more.  This  wind-blown 
material,  called  loess,  represents  a mixture  of  all  kinds  of  material  over  which 
the  glacier  passed. 

After  the  loessal  material  was  deposited  over  the  country,  the  surface 
stratum  became  mixed  with  more  or  less  organic  matter  and  thus  was  gradu- 
ally changed  into  soil.  Surface  washing  has  produced  other  changes. 

JThe  Sangamon  soil  may  sometimes  be  seen  in  cuts  as  a somewhat  dark  or  bluish  sticky 
clay  or  a weathered  zone  of  yellowish  or  brownish  clay. 


191S ) 


McDonough  County 


3 


The  soils  of  McDonough  county  are  divided  into  the  three  following 
classes : 

(1)  Upland  prairie  soils,  rich  in  organic  matter.  These  were  originally 
covered  with  wild  prairie  grasses,  the  partially  decayed  roots  of  which  have 
been  the  source  of  the  organic  matter.  The  flat,  naturally  poorly  drained 
prairie  land  contains  the  higher  amount  of  organic  matter  because  the  grasses 
and  roots  grew  more  luxuriantly  there  and  were  largely  preserved  from  de- 
cay by  the  higher  moisture  content  of  the  soil. 

(2)  Upland  timber  soils,  including  those  zones  along  stream  courses  over 
which  the  forests  once  extended.  These  soils  contain  much  less  organic  mat- 
ter than  the  upland  prairie  soils  because  the  large  roots  of  dead  trees  and  the 
surface  accumulations  of  leaves,  twigs,  and  fallen  trees  were  burned  by  for- 
est fires  or  suffered  almost  complete  decay.  The  timber  lands  are  divided 
chiefly  into  two  classes — the  undulating  and  the  hilly  areas. 

(3)  Swamp  and  bottom-land  soils,  which  include  the  flood  plains  along 
streams. 

Table  1 shows  the  area  of  each  type  of  soil  in  McDonough  county  and 
its  percentage  of  the  total  area.  It  will  be  noted  that  the  common  prairie 
soil  (the  brown  silt  loam)  occupies  55  percent  of  the  area  of  the  county, 
while  the  yellow  silt  loam  of  the  hilly  land  is  the  next  most  extensive  type, 
covering  25  percent  of  the  county. 


Table  1.— Soil  Types  of  McDonough  County 


Soil 

type 

No. 

Name  of  type 

Area  in 
square 
miles 

Area 

in 

acres 

Percent 

of 

total  area 

526 

(a)  Upland  Prairie  Soils  (page  22) 

Brown  silt  loam.  

318.18 

203  637 

55.44 

520 

Black  clay  loam 

19.22 

12  301 

3.35 

528 

Brown-gray  silt  loam  on  tight  clay 

29.25 

18  720 

5.10 

525.1 

Black  silt  loam  on  clay 

7.24 

4 634 

1.26 

535 

(b)  Upland  Timber  Soils  (page  27) 

Yellow  silt  loam  

144.41 

92  422 

25.16 

534 

Y ellow-gray  silt  loam 

39.00 

24  960 

6.79 

532 

Light  gray  silt  loam  on  tight  clay  

2.53 

1 619 

.44 

1326 

(c)  Swamp  and  Bottom-Land  Soils  (page  34) 
Deep  brown  silt  loam 

14.02 

8 973 

2.44 

(d)  Miscellaneous 

Lake 

.10 

64 

.02 

Total 

573.95 

367  330 

100.00 

The  accompanying  maps  show  the  location  and  boundary  lines  of  every 
type  of  soil  in  the  county,  even  down  to  areas  of  a few  acres;  and  in  Table  2 
are  reported  the  amounts  of  organic  carbon  (the  best  measure  of  the  organic 
matter)  and  the  total  amounts  of  the  five  important  elements  of  plant  food 
contained  in  2 million  pounds  of  the  surface  soil  of  each  type  (the  plowed 
soil  of  an  acre  about  6%  inches  deep).  In  addition,  the  table  shows  the 
amount  of  limestone  present,  if  any,  or  the  amount  of  limestone  required  to 
neutralize  the  acidity  existing  in  the  soil.1 

‘The  figures  given  in  Table  2 (and  in  the  corresponding  tables  for  subsurface  and  sub- 
soil) are  the  averages  for  all  determinations,  with  some  exceptions  of  limestone  present  or 
required.  Some  soil  types,  particularly  those  which  are  subject  to  erosion,  may  vary  from 
acid  to  alkaline,  especially  in  the  subsurface  or  subsoil ; and  in  such  cases  abnormal 
results  are  discarded,  a report  of  the  normal  conditions  being  more  useful  than  any  average 
of  figures  involving  both  plus  and  minus  quantities. 


4 


Soil  Report  No.  7 


[September, 


THE  INVOICE  AND  INCREASE  OF  FERTILITY  IN  McDONOUGH 
COUNTY  SOILS 

Soil  Analysis 

In  order  to  avoid  confusion  in  applying  in  a practical  way  the  technical 
information  contained  in  this  report,  the  results  are  given  in  the  most  simpli- 
fied form.  The  composition  reported  for  a given  soil  type  is,  as  a rule,  the 
average  of  many  analyses,  which,  like  most  things  in  nature,  show  more  or 
less  variation ; but  for  all  practical  purposes  the  average  is  most  trustworthy 
and  sufficient.  (See  Bulletin  123,  which  reports  the  general  soil  survey  of 
the  state,  together  with  many  hundreds  individual  analyses  of  soil  samples 
representing  twenty-five  of  the  most  important  and  most  extensive  soil  types 
in  the  state.) 

The  chemical  analysis  of  the  soil  gives  the  invoice  of  fertility  actually 
present  in  the  soil  strata  sampled  and  analyzed,  but,  as  explained  in  the  Ap- 
pendix, the  rate  of  liberation  is  governed  by  many  factors.  Also,  as  there 
stated,  probably  no  agricultural  fact  is  more  generally  known  by  farmers  and 
landowners  than  that  soils  differ  in  productive  power.  Even  tho  plowed  alike 
and  at  the  same  time,  prepared  the  same  way,  planted  the  same  day  with 
the  same  kind  of  seed,  and  cultivated  alike,  watered  by  the  same  rains  and 
warmed  by  the  same  sun,  nevertheless  the  best  acre  may  produce  twice  as 
large  a crop  as  the  poorest  acre  on  the  same  farm,  if  not,  indeed,  in  the  same 
field ; and  the  fact  should  be  repeated  and  emphasized  that  the  productive 
power  of  normal  soil  in  humid  sections  depends  upon  the  stock  of  plant  food 
contained  in  the  soil  and  upon  the  rate  at  which  it  is  liberated. 

The  fact  may  be  repeated,  too,  that  crops  are  not  made  out  of  nothing. 
They  are  composed  of  ten  different  elements  of  plant  food,  every  one  of 
which  is  absolutely  essential  for  the  growth  and  formation  of  every  agri- 
cultural plant.  Of  these  ten  elements  of  plant  food,  only  two  (carbon  and 
oxygen)  are  secured  from  the  air  by  all  plants,  only  one  (hydrogen)  from 
water,  while  seven  are  secured  from  the  soil.  Nitrogen,  one  of  these  seven 
elements  secured  from  the  soil  by  all  plants,  may  also  be  secured  from  the 
air  by  one  class  of  plants  (legumes)  in  case  the  amount  liberated  from  the 
soil  is  insufficient.  But  even  the  leguminous  plants  (which  include  the 
clovers,  peas,  beans,  alfalfa,  and  vetches) , in  common  with  other  agricultural 
plants,  secure  from  the  soil  alone  six  elements  (phosphorus,  potassium,  mag- 
nesium, calcium,  iron,  and  sulfur)  and  also  utilize  the  soil  nitrogen  so  far  as 
it  becomes  soluble  and  available  during  their  period  of  growth. 

Table  A in  the  Appendix  shows  the  requirements  of  large  crops  for  the 
five  most  important  plant-food  elements  which  the  soil  must  furnish.  (Iron 
and  sulfur  are  supplied  normally  from  natural  sources  in  sufficient  abundance, 
compared  with  the  amounts  needed  by  plants,  so  that  they  are  never  known 
to  limit  the  yield  of  common  farm  crops.) 

As  already  stated,  the  data  in  Table  2 represent  the  total  amounts  of 
plant-food  elements  found  in  2 million  pounds  of  surface  soil,  which  cor- 
responds to  an  acre  about  6%  inches  deep.  This  includes  at  least  as  much 
soil  as  is  ordinarily  turned  with  the  plow,  and  represents  that  part  with  which 
the  farm  manure,  limestone,  phosphate,  or  other  fertilizer  applied  in  soil  im- 
provement is  incorporated.  It  is  the  soil  stratum  that  must  be  depended  upon 


HANCOCK  COUNT1! 


Legend 

UPLAND  PRAIRIE  SOILS 

26  Brown  silt  loan 


UPLAND  TIMBER  SOILS 

[jkl  Yellow-gray  < 


532  L'eht  gfl 


SOIL  SURVEY  MAP  OF  l( 

UNIVERSITY  OF  ILLINOIS  AGRK  ; 


1 9i ■ ^ \tf>7 


AMP  AND  BOTTOM 
LAND  SOILS 


■ 


Deep  brown  silt  loam 


Scale 


: Miles 


ICDONOTIGH  COUNTY 

1/rURAL  EXPERIMENT  STATION 


F IT LT ON  COUNTY  3 


1H18  J 


McDonough  County 


5 


Tabue  2.- Fertility  in  the  Soius  of  McDonough  County 
Average  pounds  per  acre  in  2 million  pounds  of  surface  soil  (about  0 to  6%  inches) 


Soil 

type 

No. 

Soil  type 

Total 

organic 

carbon 

Total 

nitro- 

gen 

Total 

phos- 

phorus 

Total 

potas- 

sium 

Total 

magne- 

sium 

Total 

calcium 

Lime- 

stone 

present 

Lime- 

stone 

requir’d 

Upland  Prairie  Soils 

526 

Brown  silt  loam 

49  810 

4 260 

1 098 

33  090 

9 794 

11  460 

70 

520 

Black  clay  loam 

78  470 

6 167 

1 587 

29  640 

13  667 

19  673 

30 

528 

Brown-gray  silt 

loam  on  tight 

clay 

39  800 

3 400 

900 

31  740 

6 400 

8 200 

100 

525.1 

Black  silt  loam 

on  clay 

64  180 

5 420 

940 

30  960 

10  440 

15  460 

60 

Upland  Timber  Soils 


534 

Yellow-gray  silt 

27  070 

2 620 

880 

36  870 

6 270 

8 105 

70 

535 

Y ellow  silt  loam 

21  460 

2 140 

830 

37  530 

6 490 

7 060 

60 

532 

Light  gray  silt 
loam  on  tight 
clay 

16  080 

1 460 

920 

35  140 

6 420 

6 680 

140 

Swamp  and  Bottom-Land  Soils 


Deep  brown  silt 

1 1 i 

loam 

47  140 

4 580 

1 740 

37  360  1 9 140  10  960  | 

in  large  part  to  furnish  the  necessary  plant  food  for  the  production  of  crops, 
as  will  be  seen  from  the  information  given  in  the  Appendix.  Even  a rich 
subsoil  has  little  or  no  value  if  it  lies  beneath  a worn-out  surface,  for  the 
weak,  shallow-rooted  plants  will  be  unable  to  reach  the  supply  of  plant  food 
in  the  subsoil.  If,  however,  the  fertility  of  the  surface  soil  is  maintained 
at  a high  point,  then  the  plants,  with  a vigorous  start  from  the  rich  surface 
soil,  can  draw  upon  the  subsurface  and  subsoil  for  a greater  supply  of  plant 
food. 

By  easy  computation  it  will  be  found  that  the  most  common  prairie  soil 
of  McDonough  county  does  not  contain  more  than  enough  total  nitrogen  in 
the  plowed  soil  for  the  production  of  maximum  crops  for  nine  rotations  (36 
years)  ; while  the  upland  timber  soils  contain,  as  an  average,  only  one-half 
as  much  nitrogen  as  the  prairie  land. 

With  respect  to  phosphorus,  the  condition  differs  only  in  degree,  nine- 
tenths  of  the  soil  area  of  the  county  containing  no  more  of  that  element  than 
would  be  required  for  fifteen  crop  rotations  if  such  yields  were  secured  as 
are  suggested  in  Table  A of  the  Appendix.  It  will  be  seen  from  the  same 
table  that  in  the  case  of  the  cereals  about  three-fourths  of  the  phosphorus 
taken  from  the  soil  is  deposited  in  the  grain,  while  only  one-fourth  remains 
in  the  straw  or  stalks. 

On  the  other  hand,  the  potassium  is  sufficient  for  25  centuries  if  only  the 
grain  is  sold,  or  for  400  years  even  if  the  total  crops  should  be  removed  and 
nothing  returned.  The  corresponding  figures  are  about  2500  and  600  years 
for  magnesium,  and  about  15,000  and  300  years  for  calcium.  Thus,  when 
measured  by  the  actual  crop  requirements  for  plant  food,  potassium  is  no 
more  limited  than  magnesium  and  calcium,  and,  as  explained  in  the  Appen- 


Soil  Report  No.  7 


[September, 


Plate  1. — Wheat  in  1911  on  Urbana  Field 
Cover  Crops  and  Crop  Residues  Plowed  Under 
Average  Yield,  3S.2  Bushels  Per  Acre 


dix,  with  these  elements  we  must  also  consider  the  fact  that  loss  by  leaching 
is  far  greater  than  by  cropping. 

These  general  statements  relating  to  the  total  quantities  of  plant  food 
in  the  plowed  soil  certainly  emphasize  the  fact  that  the  supplies  of  some  of 
these  necessary  elements  of  fertility  are  extremely  limited  when  measured  by 
the  needs  of  large  crop  yields  for  even  one  or  two  generations  of  people. 

The  variation  among  the  different  types  of  soil  in  McDonough  county 
with  respect  to  their  content  of  important  plant-food  elements  is  also  very 
marked.  Thus,  the  richest  prairie  land,  the  black  clay  loam,  contains  about 
twice  as  much  phosphorus  and  two  to  three  times  as  much  nitrogen  as  the 
common  upland  timber  soils..  On  the  other  hand,  the  most  significant  fact 
revealed  by  the  investigation  of  the  soils  of  this  county  is  the  low  phosphorus 
content  of  the  common  brown  silt  loam  prairie,  a type  of  soil  that  covers 
more  than  half  the  entire  county.  The  market  value  of  this  land  is  about 
$200  an  acre,  and  yet  an  application  of  forty  dollars’  worth  of  fine-ground 


z f H HANCOCK  COUNTS 


LEGEND 

UPLAND  PRAIRIE  SOILS 


g26  I Brown  silt  loam’ 

H Buck  ='*>' |oam 

1^1  Brown -gray  silt  loam  on  tight  clay 
. Black  silt  loam  on  clay. 


UPLAND  TIMBER  SOILS 

3^1  Yellow-gray  silt  loam 


I ^2  Light  gray  silt  loam  on  tight  < 


SOIL  SURVEY  MAP  OF 

UNIVERSITY  OF  ILLINOIS  AGRIC 


1 


I i326i  Deep  brown  silt  loam 


l- 


CDONOUGH  COUNTY 

TURAL  EXPERIMENT  STATION 


i 


FULTON  COUNTY 


McDonough  County 


7 


1913 ] 


Plate  2. — Wheat  in  1911  on  Urbana  Field 
Cover  Crops  and  Crop  Residues  Plowed  Under 
Fine-Ground  Rock  Phosphate  Applied 
Average  Yield,  50.1  Bushels  Per  Acre 


raw  rock  phosphate  would  double  the  phosphorus  content  of  the  plowed  soil, 
and,  if  properly  made,  would  in  the  near  future  double  the  yield  of  clover. 
If  the  clover  were  then  returned  to  the  soil,  either  directly  or  in  farm  manure, 
the  combined  effect  of  phosphorus  and  increased  nitrogenous  organic  matter, 
with  a good  rotation  of  crops,  would  in  time  double  the  yield  of  corn  on  most 
farms.  The  same  treatment  would  produce  equally  good  results  on  the  un- 
dulating upland  timber  soils. 

With  more  than  4000  pounds  of  nitrogen  in  the  prairie  soil  and  an  in- 
exhaustible supply  in  the  air,  with  33,000  pounds  of  potassium  in  the  same 
soil,  and  with  practically  no  acidity,  the  economic  loss  in  farming  such  land 
with  only  1100  pounds  of  total  phosphorus  in  the  plowed  soil  can  be  ap- 
preciated only  by  the  man  who  fully  realizes  that  in  less  than  one  generation 
the  crop  yields  could  be  doubled  by  adding  phosphorus, — without  change  of 
seed  or  season  and  with  very  little  more  work  than  is  now  devoted  to  the 


8 


Soil  Report  No.  7 


[September, 


Plate  3.— Wheat  in  1911  on  Urbana  Field 
Cover  Crops  and  Farm  Manure  Plowed  Under 
Average  Yield,  34.2  Bushels  Per  Acre 

fields.  Fortunately,  some  definite  field  experiments  have  already  been  con- 
ducted on  this  most  extensive  type  of  soil,  both  in  the  upper  Illinois  glacia- 
tion in  Knox  county  and  on  similar  soil  in  the  early  Wisconsin  glaciation,  as 
at  Urbana  in  Champaign  county,  at  Sibley  in  Ford  county,  and  at  Blooming- 
ton in  McLean  county. 

Results  of  Field  Experiments  at  Urbana 

A three-year  rotation  of  corn,  oats,  and  clover  was  begun  on  the  North 
Farm  at  the  University  of  Illinois  in  1902,  on  three  fields  of  typical  brown 
silt  loam  prairie  land  which,  after  twenty  years  or  more  of  pasturing,  had 
grown  corn  in  1895,  1896,  and  1897  (when  careful  records  were  kept  of 
the  yields  produced)  and  had  then  been  cropped  with  clover  and  grass  on 
one  field,  oats  on  another,  and  oats,  cowpeas,  and  corn  on  the  third  field, 
until  1901.  As  an  average  of  the  first  three  years  (1902-1904)  phosphorus 


191S ] 


McDonough  County 


9 


Peate  4. — Wheat  in  1911  on  Urbana  Fieed 
Cover  Crops  and  Farm  Manure  Peowed  Under 
Fine-Ground  Rock  Phosphate  Appeied 
Average  Yieed,  51.8  Bushees  Per  Acre 


increased  the  crop  yields  per  acre  by  .68  ton  of  clover,  8.8  bushels  of  corn, 
and  1.9  bushels  of  oats.  During  the  second  three  years  (1905-1907)  it  pro- 
duced average  increases  of  .79  ton  of  clover,  13.2  bushels  of  corn,  and  11.9 
bushels  of  oats.  During  the  third  course  of  the  rotation  (1908-1910)  it  pro- 
duced average  increases  of  1.05  tons  of  clover,  18.7  bushels  of  corn,  and  8.4 
bushels  of  oats.  For  convenient  reference  the  results  are  summarized  in 
Table  3. 

Wheat  is  grown  on  the  University  South  Farm  in  a rotation  experiment 
started  more  recently.  As  an  average  of  the  four  years  1908  to  1911,  raw 
rock  phosphate  (with  no  previous  application  of  bone  meal)  increased  the 
yield  of  wheat  by  10.3  bushels  per  acre.  Here,  too,  as  an  average  of  the 
four  years,  the  phosphorus  applied  paid  back  about  twice  its  cost.  In  the 
grain  system  of  farming,  the  yield  of  wheat  in  1911  was  35.2  bushels  per 


10 


Soil  Report  No.  7 


[ September , 


acre  where  cover  crops  and  crop  residues  are  plowed  under  without  the  use 
of  phosphorus;  but  where  rock  phosphate  is  used  the  average  yield  was 
50.1  bushels  (see  Plates  1 and  2).  In  the  live-stock  system,  the  yield  of  wheat 
in  19 1 1 was  34.2  bushels  where  manure  and  cover  crops  are  used  without 
phosphate;  and  51.8  bushels,  as  an  average,  where  rock  phosphate  is  used  in 
addition  (see  Plates  3 and  4).  These  results  emphasize  the  cumulative  effect 
of  permanent  systems  of  soil  improvement. 


Table  3. — Effect  of  Phosphorus  on  Brown  Silt  Loam  at  Urbana 
(Average  increase  per  acre) 


Rotation 

Years 

Corn, 

bu. 

Oats, 

bu. 

Clover, 

tons 

Value  of 
increase1 

Cost  of 
treatment1 

First 

1902,-3,-4 

8.8 

1.9 

.68 

$ 7.73 

$7.50 

Second  

1905,-6,-7 

13.2 

11.9 

.79 

12.93 

7.50 

Third 

1908,-9,-10 

18.7 

8.4 

1.05 

15.37 

7.17 

‘Prices  used  are  35  cents  a bushel  for  corn,  30  cents  for  oats,  $6  a ton  for  clover 
hay,  10  and  3 cents  a pound,  respectively,  for  phosphorus  in  bone  meal  and  in  rock 
phosphate.  (Only  steamed  bone  meal  was  used  from  1902  to  19J7,  but  subsequently  three 
times  as  much  rock  phosphate  has  been  used,  at  less  cost,  on  one  half  of  each  phosphor- 
us plot.) 


Wheat  has  also  been  grown  on  the  North  Farm  during  the  last  three 
years  ( 191 1,  ’12,  ’13),  and  the  average  increase  produced  by  phosphorus  (part 
in  bone  meal  and  part  in  raw  phosphate)  has  been  12.4  bushels  per  acre  per 
year. 

Results  of  Experiments  on  Sibley  Field 

Table  4 gives  the  results  obtained  during  the  past  eleven  years  from  the 
Sibley  soil  experiment  field  located  in  Ford  county  on  the  typical  brown  silt 
loam  prairie  of  the  Illinois  corn  belt. 

Previous  to  1902  this  land  had  been  cropped  with  corn  and  oats  for  man) 
years  under  a system  of  tenant  farming,  and  the  soil  had  become  somewhat 
deficient  in  active  organic  matter.  While  phosphorus  was  the  limiting  ele- 
ment of  plant  food,  the  supply  of  nitrogen  becoming  available  annually  was 
but  little  in  excess  of  the  phosphorus,  as  is  well  shown  by  the  corn  yields  for 
1903,  when  the  addition  of  phosphorus  produced  an  increase  of  8 bushels, 
nitrogen  produced  no  increase,  but  nitrogen  and  phosphorus  together  in- 
creased the  yield  by  15  bushels. 

After  six  years  of  additional  cropping,  however,  nitrogen  appeared  to 
become  the  most  limiting  element,  the  increase  in  the  corn  in  1907  being 
9 bushels  from  nitrogen  and  only  5 bushels  from  phosphorus,  while  both 
together  produced  an  increase  of  33  bushels.  By  comparing  the  corn  yields 
for  the  four  years  1902,  1903,  1906,  and  1907,  it  will  be  seen  that  the 
untreated  land  has  apparently  grown  less  productive,  whereas,  on  land  re- 
ceiving both  phosphorus  and  nitrogen  the  yield  has  appreciably  increased, 
so  that  in  1907,  when  the  untreated  rotated  land  produced  only  34  bushels 
of  corn  per  acre,  a yield  of  72  bushels  (more  than  twice  as  much)  was  pro- 
duced where  lime,  nitrogen,  and  phosphorus  had  been  applied,  altho  the  two 
plots  produced  exactly  the  same  yield  (57.3  bushels)  in  1902. 

Even  in  the  unfavorable  season  of  1910,  the  yield  of  the  highest  produc- 
ing plot  exceeded  the  yield  of  the  same  plot  in  1902,  while  the  untreated  land 
produced  less  than  half  as  much  as  it  produced  in  1902.  The  prolonged 
drouth  of  1911  resulted  in  almost  a failure  of  the  corn  crop,  but  nevertheless 


McDonough  County 


11 


101S ] 


Tabus  4. — Crop  Yieuds  in  Soiu  Experiments,  Sibuey  Fieud 


Brown  silt  loam  prairie; 
early  Wisconsin 
glaciation 

Corn 

1902 

Corn 

1903 

Oats 

1904 

Wheat 

1905 

Corn 

1906 

Icorn 

1907 

Oats 

1908 

Wheat 

1909 

Corn 

1910 

Corn 

1911 

Oats 

1912 

Plot 

Soil  treatment 
* applied 

Bushels  per  acre 

101 

None 

57.3 

50.4 

74.1 

29.5 

36.7 

33.9 

25.9 

25.3 

26.6 

20.7 

84.4 

102 

Eime 

60.0 

54.0 

74.7 

31.7 

39.2 

38.9 

24.7 

28.8 

34.0 

22.2 

85.6 

103 

Lime,  nitrogen  . . 

60.0 

54.3 

77.5 

32.8 

41.7 

48.1 

36.3 

19.0 

29.0 

22.4 

25.3 

104 

Lime,  phosphorus 
Lime,  potassium. 

61.3 

62.3 

92.5 

36.3 

44.8 

43.5 

25.6 

32.2 

52.0 

31.6 

92.3 

105 

56.0 

49.9 

74.4 

30.2 

37.5 

34.9 

22.2 

23.2 

34.2 

21.6 

83.1 

106 

Lime,  nitrogen, 
phosphorus . . . 

57.3 

69.1 

88.4 

45.2 

68.5 

72.3 

45.6 

33.3 

55.6 

35.3 

42.2 

107 

Lime,  nitrogen, 
potassium. . . . 

53.3 

51.4 

75.9 

37.7 

39.7 

51.1 

42.2 

25.8 

46.2 

20.1 

55.6 

108 

Lime,  phosphorus, 
potassium. 

58.7 

60.9 

80.0 

39.8 

41.5 

39.8 

27.2 

28.5 

43.0 

31.8 

79.7 

109 

Lime,  nitrogen, 
phos.,  potas. . . 

58.7 

65.9 

82. 5I 

48.0 

69.5 

80.1 

52.8 

35.0 

58.0 

35.7 

57.2 

110 

Nitro.,  phos., 
potassium  . . - 

60.0 

60.1 

85.  o| 

48.5 

63.3 

72.3 

44.1 

30.8 

64.4 

31.5 

54.1 

Average  Increase:  Bushels  per  Acre 


For  nitrogen 

-1.7 

3.4 

.7 

6.4 

14.1 

23.6 

19.3 

.1 

6.4 

1.6 

-40.1 

For  phosphorus 

1.7 

12.1 

10.7 

9.2 

16.5 

15.7 

6.4 

8.1 

16.3 

12.0 

5.4 

For  potassium 

For  nitro.,  phos.,  over 

-3.0 

-2.9 

—5.1 

2.4 

—1.5 

1.0 

3.0 

- .2 

2.7 

— .6 

7.5 

phos 

For  phos.,  nitro.  over 

-4.0 

6.8 

—4.1 

8.9 

23.7 

28.8 

20.0 

1.1 

3.6 

3.7 

-50.1 

nitro 

—2.7 

14.8 

10.9 

12.4 

26.8 

24.2 

9.3 

14.3 

26.6 

12.9 

16.9 

For  potas.,  nitro.,  phos. 

over  nitro.,  phos. . . . 

1.4 

-3.2 

—5.9 

2.8 

1.0 

7.8 

7.2 

1.7 

2.4 

.4 

15.0 

Value  of  Crops  per  Acre  in  Eleven  Years 


Plot 

Soil  treatment  applied 

Total  value  of 
eleven  crops 

Value  of 
increase 

101 

102 

None. 

$ 172.73 
184.75 

$ 12.03 

103 

104 

105 

L/ime,  nitrogen  

167.42 

214.50 

173.22 

— 5.31 
41.77 

.49 

Lime,  phosphorus 

Lime,  potassium.  

106 

107 

108 

Lime,  nitrogen,  phosphorus 

233.15 

188.19 

200.37 

60.42 

15.46 

27.64 

Lime,  nitrogen,  potassium 

Lime,  phosphorus,  potassium 

109 

110 

Lime,  nitrogen,  phosphorus,  potassium 

244.62 

233.54 

71.89 

60.81 

Nitrogen,  phosphorus,  potassium 

Value  of  Increase  per  Acre  in  Eleven  Years 

Cost  of 
increase 

For  n 
For  p 
For  n 
For  p 
For  / 
a 

itrogen 

hosphorus 

itrogen  and  phosphorus  over  phosphorus 

hosphorus  and  nitrogen  over  nitrogen 

wtassium,  nitrogen,  and  phosphorus  over  nitrogen 
md  phosphorus  t 

$-17.33 

29.75 

18.65 

65.73 

11.47 

$ 165.00 
27.50 
165.00 
27.50 

27.50 

12 


Soil  Eepoet  No.  7 


[September, 


the  effect  of  soil  treatment  was  seen.  Phosphorus  appeared  to  be  the  first 
limiting  element  again  in  1909,  1910,  and  1911;  while  the  lodging  of  oats, 
especially  on  the  nitrogen  plots,  in  the  exceptionally  favorable  season  of  1912, 
produced  very  irregular  results. 

In  the  lower  part  of  Table  4 are  shown  the  total  values  per  acre  of  the 
eleven  crops  from  each  of  the  ten  different  plots,  the  amounts  varying 
from  $167.42  to  $244.62;  also  the  value  of  the  increase  produced  in  crop 
yields  above  the  value  of  the  yields  from  the  untreated  land,  corn  being  val- 
ued at  35  cents  a bushel,  oats  at  30  cents,  and  wheat  at  70  cents.  Phos- 
phorus without  nitrogen  has  produced  $29.75  in  addition  to  the  increase  by 
lime;  but  with  nitrogen  it  has  produced  $65.73  above  the  crop  values  where 
only  lime  and  nitrogen  have  been  used.  The  results  show  that  in  25  cases 
out  of  44  the  addition  of  potassium  has  decreased  the  crop  yields.  Even 
under  the  most  favorable  conditions,  and  with  no  effort  to  liberate  potassium 
from  the  soil  by  adding  organic  matter,  potassium  has  paid  back  less  than 
half  its  cost. 

By  comparing  Plots  101  and  102,  and  also  109  and  no,  it  will  be  seen 
that  lime  has  produced  an  average  increase  of  $11.55,  or  more  than  $1  an 
acre  a year.  Altho  this  increase  may  have  been  above  normal  on  these  plots 
because  of  the  condition  of  the  soil  at  the  beginning  of  the  experiment,  it 
suggests  that  the  time  is  here  when  limestone  must  be  applied  to  some  of  these 
brown  silt  loam  soils. 

While  nitrogen,  on  the  whole,  has  produced  an  appreciable  increase,  es- 
pecially on  those  plots  to  which  phosphorus  has  also  been  added,  it  has.  cost, 
in  commercial  form,  so  much  above  the  value  of  the  increase  produced  that 
the  only  conclusion  to  be  drawn,  if  we  are  to  utilize  this  fact  to  advantage, 
is  that  the  nitrogen  must  be  secured  from  the  air. 

Results  op  Experiments  on  Bloomington  Field 

Space  is  taken  to  insert  Table  5,  giving  all  the  results  thus  far  obtained 
from  the  Bloomington  soil  experiment  field,  which  is  also  located  on  the 
brown  silt  loam  prairie  soil  of  the  Illinois  corn  belt. 

The  general  results  of  the  eleven  years’  work  on  the  Bloomington  field 
tell  much  the  same  story  as  those  from  the  Sibley  field.  The  rotations  have 
differed  since  1905  by  the  use  of  clover  and  the  discontinuing  of  the  use  of 
commercial  nitrogen  on  the  Bloomington  field ; in  consequence  of  which  phos- 
phorus without  commercial  nitrogen,  on  the  Bloomington  field,  has  produced 
an  even  larger  increase  ($89.92)  than  has  been  produced  by  phosphorus  and 
nitrogen  over  nitrogen  on  the  Sibley  field  ($65.73). 

It  should  be  stated  that  a draw  runs  near  Plot  no  on  the  Bloomington 
field,  that  the  crops  on  that  plot  are  sometimes  damaged  by  overflow  or  im- 
perfect drainage,  and  that  Plot  101  occupies  the  lowest  ground  on  the  oppo- 
site side  of  the  field.  In  part  because  of  these  irregularities  and  in  part  be- 
cause only  one  small  application  has  been  made,  no  conclusions  can  be  drawn 
in  regard  to  lime.  Otherwise  all  results  reported  in  Table  5 are  considered 
reliable.  They  not  only  furnish  much  information  in  themselves,  but  they 
also  offer  instructive  comparison  with  the  Sibley  field. 

Wherever  nitrogen  has  been  provided,  either  by  direct  application  or  by  the 
use  of  legume  crops,  the  addition  of  the  element  phosphorus  has  produced 
very  marked  increases,  the  average  yearly  increase  for  the  Bloomington  field 
being  worth  $7.11  an  acre.  This  is  $4.61  above  the  cost  of  the  phosphorus 


1913 ] 


McDonough  County 


13 


Tabus  S Crop  Yields  in  Soil  Experiments,  Bloomington  Field 


Brown  silt  loam  prairie; 
early  Wisconsin 
glaciation 

Corn 

1902 

Corn 

1903 

Oats 

1904 

Wheat  Clover 
1905  | 1906 

Corn 

1907 

Corn 

19v.8 

Oats 

1909 

Clover2 

1910 

Wheat  Com 
1911  | 1912 

o 

s 

Soil  treatment 
applied 

Bushels  or  tons  per 

acre 

101 

None 

30.8 

63.9 

54.8 

30.8 

.39 

60.8 

40.3 

46.4 

1.56 

22.5 

55.2 

102 

Lime 

37.0 

60.3 

60.8 

28.8 

.58- 

63.1 

35.3 

53.6 

1.09 

22.5 

47.9 

103 

Lime,  crop  res.1  .... 

35.1 

59.5 

69.8 

30.5 

1 .46 

64.3 

36.9 

49.4 

(.83) 

25.6 

62.5 

104 

Lime,  phosphorus. . 

41.7 

73.0 

72.7 

39.2 

1.65 

82.1 

47.5 

63.8 

4.21 

57.6 

74.5 

105 

Lime,  potassium  . . . 

37.7 

56.4 

62.5 

1 33'2 

.51 

64.1 

36.2 

45.3 

1.26 

21.7 

£7.8 

106 

Lime,  residues,1 

phosphorus 

43.9 

77.6 

85.3 

50.9 

3 

78.9 

45.8 

72.5 

(1.67) 

60.2 

86.1 

107 

Lime,  residues,1 
potassium 

40.4 

58.9 

66.4 

29.5 

.81 

64.3 

31.0 

51.1 

(.33) 

27.3 

58.9 

108 

Lime,  phosphorus, 
potassium 

50.1 

74.8 

70.3 

37.8 

2.36 

81.4 

57.2 

59.5 

3.27 

54.0 

73.2 

109 

Lime,  res.,1  phos., 

52.7 

80.9 

90.5 

51.9 

8 

88.4 

58.1 

64.2 

(.42) 

60.4 

83,4 

110 

potassium 

Res.,  phosphorus, 

52.3 

73.1 

71.4 

51.1 

3 

78.  OJ 

51.4 

55.3 

(.60) 

61.0 

78.3 

potassium 

Average  Increase:  Bushels  or  Tons  per  Acre 


For  residues  

1.4 

3.1 

11.4 

5.9 

-.96 

1.3 

-l.i 

3.7 

-1.64 

4.4 

7.9 

For  phosphorus 

9.5 

17.8 

14.8 

14.4 

.41 

18.8 

18.0 

15.1 

1.51 

33.9 

24.0 

For  potassium 

5.8 

.2 

.3 

.7 

.25 

2.4 

4.2 

-4.8 

-.63 

— .6 

2.1 

For  res., phos. overphos. 

2.2 

4.6 

12.6 

11.7 

-1.65 

-3.2 

-1.7 

8.7 

-2.25 

2.6 

11.6 

For  phos., res.  over  res. 
For  potas.,  res.,  phos. 

8.8 

18.1 

15.5 

20.4 

- .46 

14.6 

8.9 

23.1 

.84 

34.6 

23.6 

over  res.,  phos 

8.8 

3.3 

5.2 

1.0 

.00 

9.5 

12.3 

-8.3 

-1.25 

.2 

-2.7 

Value  of  Crops  per  Acre  in  Eleven  Years 


o 

Soil  treatment  applied 

Total  valued 

Value  of 

s 

eleven  crops 

increase 

io: 

None 

8167.22 

102 

Lime 

165.52 

—$1.70 

:t03 

Lime,  residues 

173.17 

5.95 

104 

Lime,  phosphorus 

255.44 

88.22 

105 

Lime,  potassi  :m  

169.66 

2.44 

106 

Lime,  residues,  phosphorus 

Lime,  residues,  potassium 

251.43 

84.21 

107 

170.57 

3.36 

108 

Lime,  phosphorus,  potassium 

256.92 

[ 89.70 

109|  Lime,  residues,  phosphorus,  potassium 

254.76 

87.54 

r.j 

1 Residues,  phosphorus,  potassium 

236.66 

69.44 

■ 

Value  of  Increase  per  Acre  in  Eleven  Years 

| Cost  of 
increase 

For  residues 

$ 7.65 

? 

For  phosphorus 

89.92 

$27.50 

For  residues  and  phosphorus  over  phosphorus 

—4.01 

? 

F or  phosphorus  and  residues  over  residues 

For  potassium,  residues,  and  phosphorus  over  residues 

78.26 

27.50 

and  phosphorus 

3.33 

27.50 

‘Commercial  nitrogen  was  used  1902-1905. 

9The  figures  in  parentheses  mean  bushels  of  seed;  the  others,  tons  of  hay. 
•Clover  smothered  by  previous  wheat  crop. 


14 


Soil  Beport  No.  7 


[September, 


in  200  pounds  of  steamed  bone  meal,  the  form  in  which  it  is  applied  to  the 
Sibley  and  the  Bloomington  fields.  On  the  other  hand,  the  use  of  phosphorus 
without  nitrogen  will  not  maintain  the  fertility  of  the  soil  (see  Plots  104  and 
106,  Sibley  field).  As  the  only  practical  and  profitable  method  of  supplying 
nitrogen,  a liberal  use  of  clover  or  other  legumes  is  suggested,  the  legume 
to  be  plowed  under  either  directly  or  as  manure,  preferably  in  connection 
with  the  phosphorus  applied,  especially  if  raw  rock  phosphate  is  used. 

From  the  soil  of  the  best  treated  plots  on  the  Bloomington  field,  160 
pounds  per  acre  of  phosphorus,  as  an  average,  have  been  removed  in  the  eleven 
crops.  This  is  equal  to  more  than  13  percent  of  the  total  phosphorus  con- 
tained in  the  surface  soil  of  an  acre  of  the  untreated  land.  In  other  words, 
if  such  crops  could  be  grown  for  eighty  years,  they  would  require  as  much 
phosphorus  as  the  total  supply  in  the  ordinary  plowed  soil.  The  results  plainly 
show,  however,  that  without  the  addition  of  phosphorus  such  crops  cannot 
be  grown  year  after  year.  Where  no  phosphorus  has  been  applied,  the  crops 
have  removed  only  107  pounds  of  phosphorus  in  the  eleven  years,  which  is 
equivalent  to  only  9 percent  of  the  total  amount  (1,200  pounds)  that  was 
present  in  the  surface  soil  at  the  beginning  of  the  experiment  in  1902.  The 
total  phosphorus  applied  from  1902  to  1912,  as  an  average  of  all  plots  where 
it  has  been  used,  has  amounted  to  275  pounds  per  acre  and  has  cost  $27.50. 
This  has  paid  back  $84.91,  or  300  percent  on  the  investment;  whereas 
potassium,  used  in  the  same  number  of  tests  and  at  the  same  cost,  has  paid 
back  only  $1.59  per  acre  in  the  eleven  years,  or  less  than  6 percent  of  its  cost. 
Are  not  these  results  to  be  expected  from  the  composition  of  the  soil  and 
the  requirements  of  crops?  (See  Table  2,  page  5,  and  also  Table  A in  the 
Appendix. ) 

Nitrogen  was  applied  to  this  field,  in  commercial  form  only,  from  1902 
to  1905 ; but  clover  was  grown  in  1906  and  1910,  and  a catch  crop  of  cow- 
peas  after  the  clover  in  1906.  The  cowpeas  were  plowed  under  on  all  plots, 
and  the  1910  clover  (except  the  seed)  was  plowed  under  on  five  plots  ^103, 
106,  107,  109,  and  no).  Straw  and  corn  stalks  have  also  been  returned 
to  these  plots  in  recent  years.  The  effect  of  returning  these  residues  to  the 
soil  is  already  appreciable  (an  average  increase  of  4.4  bushels  of  wheat  in 
1911  and  7.9  bushels  of  corn  in  1912)  and  probably  will  be  more  marked 
on  subsequent  crops.  Indeed,  the  large  crops  of  corn,  oats,  and  wheat  grown 
on  Plots  104  and  108  during  the  eleven  years  have  drawn  their  nitrogen  very 
largely  from  the  natural  supply  in  the  organic  matter  of  the  soil.  The  roots 
and  stubble  of  clover  contain  no  more  nitrogen  than  the  entire  plant  takes 
from  the  soil  alone,  but  they  decay  rapidly  in  contact  with  the  soil  and  prob- 
ably hasten  the  decomposition  of  the  soil  humus  and  the  consequent  libera- 
tion of  the  soil  nitrogen.  But  of  course  there  is  a limit  to  the  reserve  stock 
of  humus  and  nitrogen  remaining  in  the  soil,  and  the  future  years  will  un- 
doubtedly witness  a gradually  increasing  difference  between  Plots  104  and 
106,  and  between  Plots  108  and  109,  in  the  yields  of  grain  crops. 

Plate  5 shows  graphically  the  relative  values  of  the  eleven  crops  for  the 
eight  comparable  plots,  Nos.  102  to  109.  The  cost  of  the  phosphorus  is  in- 
dicated by  that  part  of  the  diagram  above  the  short  crossbars.  It  should  be 
kept  in  mind  that  no  value  is  assigned  to  clover  plowed  under  except  as  it 
reappears  in  the  increase  of  subsequent  crops.  Plots  106  and  109  are  heavily 
handicapped  because  of  the  clover  failure  on  those  plots  in  1906  and  the  poor 
yield  of  clover  seed  in  1910,  whereas  Plots  104  and  108  produced  a fair 
crop  in  1906  and  a very  large  crop  in  1910.  As  an  average,  Plots  106  and 
109  are  only  $3.09  behind  Plots  104  and  108  in  the  value  of  the  eleven  crops 


191S] 


McDonough  County 


15 


102  103  104  105  106  107  108  109 

OR  P K RP  RK  PK  RPK 

$165.52  $173.17  $255.44  $169.66  $251.43  $170.57  $256.92  $254.76 

Pi, ate  5 Crop  Values  for  Eleven  Years 

Bloomington  Experiment  Field 
(R=residues;  P = phosphorus;  K=potassium,  or  kalium) 


harvested,  and  this  would  have  been  covered  by  about  Yi  bushel  more  clover 
seed  in  1906  or  1910,  or  it  may  be  covered  by  10  bushels  more  corn  in  1913. 
The  values  from  Plots  103  and  107  average  $4.28  more  than  the  values  from 
Plots  102  and  105.  (See  also  table  on  last  page  of  cover.) 

Results  of  Field  Experiments  at  Galesburg 

In  Tables  6,  7,  and  8 are  reported  in  detail  the  results  obtained  from  the 
University  of  Illinois  soil  experiment  field  near  Galesburg,  on  the  line  be- 
tween Knox  and  Warren  counties,  on  the  brown  silt  loam  prairie  soil  of  the 
upper  Illinois  glaciation. 

A six-year  rotation  has  been  practiced  on  this  field  since  1904.  During 
the  first  six  years  the  order  of  cropping  was  corn,  corn,  oats,  wheat,  followed 
by  two  years  of  clover  and  timothy.  Since  then  the  rotation  has  been  corn, 
corn,  oats,  clover,  wheat,  clover.  There  are  only  three  independent  series  of 
plots,  so  that  while  corn  is  grown  every  year  the  other  crops  are  harvested 
only  in  alternate  years,  altho  clover  should  be  on  the  field  every  year,  either 
in  the  stubble  of  the  oats  and  wheat  or  as  a regular  crop. 

Each  series  contains  twenty  individual  fifth-acre  plots,  2 rods  wide  and 
16  rods  long,  with  half-rod  division  strips  cultivated  and  cropped  between 
the  plots,  a quarter-rod  border  cultivated  and  cropped  surrounding  each 


16 


Soil  Repoet  No.  7 


[September, 


Table  6.— Crop  Yields  in  Soil  Experiments,  Galesburg  Field:  Series  100 


Brown  silt  loam  prairie; 
upper  Illinois  glaciation 

Corn 

1904 

Corn 

1905 

Oats 

1906 

[wheat 

1907 

Clo- 

ver1 

1908 

Timo- 

thy1 

1909 

Corn 

1910 

Corn 

1911 

Oats 

1912 

Plot 

Soil  treatment  applied 

Bushels  or  tons  per  acre 

101 

Lime  

63.8 

52.5 

53.8 

34.0 

2.71 

2.04 

59.8 

66.5 

53.3 

102 

Residues,  lime 

67.3 

49.8 

53.6 

41.4 

(.96) 

(3.83) 

72.6 

75.1 

56.9 

103 

Manure,  lime 

64.7 

48.1 

50.3 

31.6 

2.59 

1.83 

77.6 

81.0 

60.0 

104 

Cover  crop,  manure,  lime . . . 

65.3 

46.5 

46.7 

32.8 

2.61 

1.70 

77.9 

78.9 

70.2 

105 

Lime 

74.7 

54.9 

52.3 

35.1 

2.80 

2.05 

66.2 

67.4 

60.8 

106 

Lime,  phosphorus 

78.2 

66.1 

53.9 

41.9 

3.18 

2.58 

72.4 

79.4 

68.6 

107 

Residues,  lime,  phosphorus 

75.9 

63.1 

55.0 

41.3 

(.67) 

(4.92) 

78.0 

83.8 

65.2 

108 

Manure,  lime,  phosphorus.. 

72.6 

61.1 

54.2 

37.9 

3.18 

2.36 

74.6 

79.8 

77.3 

109 

Cover  crop,  manure,  lime, 

phosphorus 

74.1 

60.0 

54.2 

40.0 

3.15 

2.33 

74.0 

79.1 

74.4 

110 

Lime 

72.4 

58.8 

50.5 

32.7 

2.65 

1.74 

61.5 

59.2 

54.5 

111 

Lime,  phosphorus,  po- 

tassium   

81.2 

72.3 

53.9 

36.6 

3.21 

2.42 

74.5 

81.1 

70.9 

112 

Residues,  lime,  phosphorus, 

potassium 

82.3 

71.0 

59.4 

41.1 

(.58) 

(5.00) 

81.9 

83.7 

59.5 

113 

Manure,  lime,  phosphor- 

us, potassium 

77.1 

72.2 

52.8 

36.1 

3.45 

2.49 

77.6 

82.4 

74.4 

114 

Cover  crop, manure, lime, 

phos.,  potassium 

89.4 

69.9 

54.5 

38.7 

3.36 

2.55 

75.9 

85.0 

70.0 

115 

Lime 

81.2 

68.1 

62.8 

36.8 

2.99 

2.19 

59.4 

67.3 

53.0 

116 

Residues ...  

77.1 

61.8 

57.3 

38.2 

(1.17) 

(5.33) 

70.6 

68.9 

52.0 

117 

Residues,  phosphorus 

79.4 

64.2 

60.0 

36.2 

(1.25) 

(5.50) 

75.0 

77.5 

66.1 

118 

Residues,  phosphorus, 

potassium 

82.3 

70.8 

52.0 

40.9 

(1.38) 

(4.75) 

78.3 

78.4 

68.1 

119 

Residues,  lime,  nitrogen, 

phos.,  potassium 

87.1 

76.3 

66.2 

46.0 

(1.08) 

(5.00) 

74.8 

79.3 

67.3 

120 

None 

82.9 

65.1 

65.3 

45.8 

3.04 

2.82 

72.7 

67.4 

70.2 

Increase  for  residues 

—2.19 

— .89 

5.9 

4.3 

—7.3 

Increase  for  manure 

7.7 

5.4 

6.3 

Increase  for  phosphorus 

6.2 

10.7 

3.4 

3.6 

.26 

.42 

1.8 

5.7 

10.3 

Increase  for  potassium 

6.4 

8.3 

—.9 

— 8 

.11 

—.01 

2.8 

2.2 

—1.7 

Increase  for  nitrogen 

4.8 

5.5 

14.2 

5.1 

—(.30) 

(.25) 

—3.5 

.9 

—.8 

’The  figures  in  parentheses  in  these  columns  represent  bushels  of  seed;  the  others, 
tons  of  hay. 


series,  and  grass  strips  about  two  rods  wide  between  the  series  and  surround- 
ing the  experiment  field.  The  soil  treatment  for  the  individual  plots  is  in- 
dicated in  Tables  6,  7,  and  8. 

Limestone  was  applied  in  small  amount  (1300  pounds  per  acre)  to  the 
first  fifteen  plots  in  each  series  in  1904.  No  further  application  was  made 
until  the  spring  of  1912,  when  4 tons  per  acre  were  applied  to  Plots  1 to  15 
of  Series  300.  Thus  far  no  apparent  effect  has  been  produced,  but  further 
experiment  with  liberal  applications  may  show  results.  Plots  1 to  15  in 
Series  100  and  200  were  given  4 tons  per  acre  in  the  spring  of  1913. 

The  “residues”  include  the  straw  and  corn  stalks,  all  clover  except  the 
seed,  and  legume  cover  crops,  such  as  cowpeas,  soybeans,  or  vetch,  seeded  in 
the  corn  at  the  last  cultivation.  These  are  returned  to  certain  plots  in  order 
to  supply  nitrogen  and  organic  matter  in  a system  of  grain  farming.  This 
system  was  not  fully  under  way  on  all  series  until  1911,  as  may  be  seen  from 
the  lower  parts  of  Tables  6,  7,  and  8,  so  that  as  yet  no  conclusions  regarding 
this  treatment  are  justified,  except  that  it  provides  an  abundance  of  organic 
matter.  Whether  the  value  of  the  clover  plowed  under  will  ultimately  reap- 


191S] 


McDonough  County 


17 


Tabus  7 Crop  Yields  in  Son,  Experiments,  Galesburg  Field:  Series  200 


Brown  silt  loam  prairie; 
upper  Illinois  glaciation 

Oats 

1904 

Wheat 

1905 

Clover 

1906 

Timo- 

thy 

1907 

Corn 

1908 

Corn 

1909 

Oats 

1910 

Clover 

1911 

Wheat 

1912 

Plot 

Soil  treatment  applied 

Bushels  or  tons 

per  acre 

201 

Lime 

57.5 

40.5 

.72 

2.30 

79.8 

54.1 

48.0 

1.39 

17.5 

202 

Residues,  lime 

55.  C 

40.0 

.63 

1.31 

78.8 

51.9 

43.3 

21.1 

203 

Manure,  lime 

52.5 

38.5 

.57 

2.55 

101.3 

65.6 

50.6 

2.64 

21.7 

204 

Cover  crop,  manure, 

lime 

55.0 

40.2 

.63 

2.73 

102.7 

66.8 

53.0 

2.32 

19.6 

205 

Lime 

67.5 

42.2 

1.22 

2.84 

86.3 

54.4 

44.4 

2.29 

18.2 

206 

Lime,  phosphorus 

62.5 

41.3 

1.36 

3.27 

99.6 

59.1 

55.5 

2.42 

27.3 

207 

Residues,  lime,  phos- 

phorus. . 

57.5 

42.2 

.90 

1.79 

105.6 

49.4 

48.6 

27.3 

208 

Manure,  lime,  phos- 

phorus 

60.0 

40.0 

.91 

3.18 

106.6 

69.8 

58.6 

2.30 

27.3 

209 

Cover  crop,  manure, 

lime,  phos 

50.0 

39.0 

.91 

3.16 

105.8 

75.7 

60.3 

2.03 

27.8 

210 

Lime 

57.5 

37.5 

.69 

2.46 

84.5 

57.8 

42.3 

1.14 

12.2 

211 

Lime,  phosphorus,  po- 

tassium  

55.0 

38.7 

1.31 

3.38 

95.7 

67.0 

55.3 

2.01 

28.2 

212 

Residues,  lime,  phos- 

phorus, potassium . . 

65.0 

39.3 

1.40 

2.15 

103.3 

57.5 

53.8 

28.3 

213 

Manure,  lime,  phos- 

phorus, potassium.. 

65.0 

41.5 

1.79 

3.62 

98.1 

69.8 

58.3 

2.55 

25.9 

214 

Cover  crop,  manure, 

lime,  phos.,  potas. . . 

62.5 

40.7 

1.51 

3.48 

102.8 

73.3 

62.8 

2.46 

25.3 

215 

Lime 

60.0 

35.5 

.83 

2.33 

84.1 

58.2 

41.6 

.98 

8.8 

216 

Residues 

72.5 

37.0 

.82 

1.37 

87.3 

54.8 

38.6 

11.8 

217 

Residues,  phosphorus. . 

57.5 

38.7 

.85 

1.44 

98.6 

49.6 

43.4 

22.1 

218 

Residues,  phosphorus, 

potassium 

50.0 

40.7 

1.51 

2.17 

99.0 

43.0 

46.3 

28.3 

219 

Residues,  lime,  nitro- 

gen, phos.,  potas. . . . 

57.5 

37.7 

1.21 

1.98 

109.6 

47.2 

57.2 

27.3 

220 

None 

55.0 

39.5 

.71 

2.49 

88.3 

49.5 

38.1 

1.00 

15.6 

Increase  for  residues 

—3.1 

—1.70 

0.0 

Increase  for  manure 

7.7 

8.3 

2.9 

.56 

.6 

Increase  for  phosphorus 

-3.0 

.7 

.21 

.41 

12.0 

2.0 

7.3 

— .17 

7.7 

Increase  for  potassium 

2.0 

_ .1 

.52 

.39 

—3.5 

1.4 

2.0 

.09 

.8 

Increase  for  nitrogen 

7.5 

—3.0 

—.30 

— .19 

10.6 

4.2 

10.9 

—1.0 

pear  in  subsequent  yields  of  grain  and  seed,  must  be  determined  by  the 
further  accumulation  of  data.1 

Farm  manure  is  applied  to  certain  plots  (see  tables)  in  proportion  to 
their  previous  average  crop  yields ; that  is,  as  many  tons  of  manure  are  ap- 
plied to  each  plot  as  there  were  average  tons  of  air-dry  produce  removed 
from  the  corresponding  plots  during  the  previous  rotation,  but  no  manure 


A.lsike’  mammoth,  and  sweet  clover  promise  to  yield  the  better  returns  in  seed 
altho  in  some  cases  seed  has  been  threshed  from  both  the  first  and  second  cuttings 
of  the  red  clover.  It  is  quite  possible  that  better  average  results  would  be  secured  by 
regularly  removing  the  first  cutting  of  red  clover,  with  the  purpose  of  threshing  it 
for  seed,  as  well  as  the  second  cutting  if  found  advisable.  Some  splendid  seed  crops 
have  been  secured  from  the  second  cutting  when  the  first  was  clipped  and  left  on  the 
land,  but  under  other  seasonal  conditions  the  second  crop  has  been  a failure.  In  such 
cases,  altho  the  apparent  effect  is  a total  loss  of  the  clover  crop,  at  least  part  of  this 
loSS  is  recover.ed  in  subsequent  crops  of  grain.  It  should  never  be  forgotten 
the  PurP°se  this  system  is  to  enable  the  grain  farmer  to  maintain  the  fer- 
tility  of  his  soil,  even  tho  some  other  system  which  he  may  not  be  prepared  to  adout 
might  be  more  profitable.  F 


13 


Soil  Report  No.  7 


[September, 


Table  8.— Crop  Yields  in  Soil  Experiments,  Galesburg  Field:  Series  300 


Brown  silt  loam  prairie; 
upper  Illinois  glaciation 

Tim- 

othy 

1904 

Tim- 

othy 

1905 

Corn 

1906 

Corn] 

1907 

Oats 

1908 

Wheat 

1909 

Wheat 

1910 

Clover 

1911 

Corn 

1912 

Plot 

Soil  treatment  applied 

Bushels  or  tons  per  acre 

301 

Lime 

1.36 

1.54 

66.8 

75.9 

28.6 

31.7 

16.2 

2.17 

70.8 

302 

Residues,  lime 

1.38 

1.59 

68.6 

77.7 

26.6 

33.8 

19.4 

89.6 

303 

Manure,  lime 

1.30 

1.92 

72.0 

80.3 

28.3 

36.3 

19.6 

2.57 

104.3 

304 

Cover  crop,  manure, 

lime 

1.38 

2.02 

75.6 

83.1 

26.1 

40.4 

22.3 

2.03 

103.3 

305 

Lime 

1.20 

1.75 

70.5 

78.3 

22.5 

36.6 

21.2 

1.83 

92.1 

306 

Lime,  phosphorus 

1.21 

1.65 

69.7 

84.4 

32.7 

40.6 

22.2 

2.64 

98.2 

307 

Res., lime,  phosphorus 

1.16 

1.55 

74.0 

84.1 

27.5 

41.2 

24.1 

103.2 

308 

Manure,  lime,  phos- 

phorus 

1.25 

1.63 

73.9 

86.1 

33.9 

39.7 

21,6 

3.25 

107.9 

309 

Cover  crop,  manure, 

lime,  phosphorus... 

1.55 

2.03 

83.9 

87.8 

28.9 

44.9 

24.9 

3.13 

106.0 

310 

Lime 

1.75 

2.25 

84.3 

85.6 

31.6 

39.8 

22.4 

2.74 

93.0 

311 

Lime,  phosphorus,  po- 

tassium  

2.10 

2.41 

86.9 

87.8 

32.3 

44.3 

24.5 

3.59 

101.9 

312 

Residues,  lime,  phos- 

phorus, potassium.. 

1.55 

1.91 

75.8 

81.2 

25.9 

41.8 

23.2 

98.4 

313 

Manure,  lime,  phos- 

phorus, potassium.  . 

1.16 

1.53 

68.4 

77.9 

31.3 

35.8 

23.0 

3.28 

108.8 

314 

Cover  crop,  manure, 

lime,  phos.,  potas. . . 

1.50 

1.52 

70.6 

81.7 

27.7 

42.0 

23.1 

3.57 

106.9 

315 

Lime 

1.90 

1.97 

74.1 

85.1 

30.6 

36.8 

21.6 

2.47 

90.6 

316 

Residues 

1.82 

1.82 

67.7 

80.6 

26.7 

34.2 

22  9 

82.1 

317 

Residues,  phosphorus. 

1.95 

2.00 

59.1 

83.3 

31.1 

44.9 

27.0 

99.2 

318 

Residues,  phosphorus, 

potassium 

2.65 

2.18 

66.8 

73.6 

25.8 

43.3 

29.1 

113.2 

319 

Residues,  lime,  nitro- 

gen, phos.,  potas. . . . 

4.15 

2.37 

71.2 

84.7 

32.7 

43.8 

24.9 

104.1 

320 

None 

1.46 

1.56 

59.6 

72.8 

31.3 

28.5 

15.8 

1.46 

| 79.1 

Increase  for  residues 

—2.46 

5.8 

Increase  for  manure 

16.7 

Increase  for  phosphorus 

.01 

-.05 

1.2 

5.1 

4.8 

6.0 

2.9 

.86 

8.6 

Increase  for  potassium  

.37 

.14 

A- 6 

—4.7 

2.2 

-.8 

.6 

.47 

2.9 

Increase  for  nitrogen.. 

1.50 

.19 

4.4 

11.1 

6.9 

.5 

-4.2 

-9.1 

was  used  until  crops  had  been  grown  for  four  years  and  the  data  had  been 
thus  accumulated  from  which  to  compute  the  proper  applications  of  manure. 
The  live-stock  system  was  not  fully  under  way  on  all  series  until  1912  (see 
lower  parts  of  tables),  when  the  average  increase  from  the  manure  varied 
from  bushel  of  wheat  to  nearly  17  bushels  of  corn. 

On  Plots  4,  9,  and  14  cover  crops  are  grown  as  indicated  in  the  tables, 
but  the  results  thus  far  secured  do  not  justify  advising  this  practice,  as  may 
be  seen  by  comparing  these  plots  -with  Plots  3,  8,  and  13,  respectively. 

At  the  beginning  of  this  experiment  this  field  was  all  in  timothy  sod. 
Series  300  was  not  broken  during  the  first  two  years,  but  ^4  ton  of  raw  rock 
phosphate  per  acre  was  applied  as  top-dressing.  This  produced  practically 
no  effect, — a result  to  be  expected.  A ton  of  phosphate  per  acre  applied  to 
Series  200  produced  no  effect  on  the  oats  seeded  on  timothy  sod  in  1904  and 
but  little  effect  on  the  wheat  which  followed  in  1905.  Beginning  with  Series 
100  in  1904,  Series  300  in  1906,  and  Series  200  in  1908,  the  regular  plan  has 
been  to  apply  1 >4  tons  of  raw  rock  phosphate  (375  pounds  of  phosphorus) 
per  acre  every  six  years  /before  plowing  for  corn,  in  addition  to  the  partial 
applications  made  as  stated  above.  This  plan  has  been  followed  essentially, 


1918 ] 


McDonough  County 


19 


and  will  be  continued  until  the  phosphorus  content  of  the  plowed  soil  is  at 
least  doubled,  but  ultimately  the  amounts  applied  for  each  rotation  will  be 
reduced  to  supply  only  about  as  much  as  is  removed  in  the  crops  grown,  and 
of  course  the  annual  expense  for  this  element  will  then  decrease  accordingly. 

Potassium  is  applied  in  the  form  of  potassium  sulfate,  ioo  pounds  per 
acre  of  the  sulfate  (containing  42  pounds  of  potassium)  being  used  for  each 
year  in  the  rotation.  The  application  is  made  only  in  connection  with  the 
phosphate  in  order  to  ascertain  whether  its  use  in  this  way  is  profitable,  there 
being  no  doubt  that  it  would  be  unprofitable  if  used  alone. 

In  order  to  help  settle  the  question  whether  commercial  nitrogen  could 
be  used  with  profit,  Plot  19  in  each  series  has  received  nitrogen  at  the  rate 
of  25  pounds  per  acre  per  annum.  Nearly  the  total  amount  for  the  first  four 
years  was  applied  in  1904,  but  since  1907  the  applications  have  been  made 
annually.  The  nitrogen  has  been  applied  in  addition  to  crop  residues,  phos- 
phorus, potassium,  and  limestone. 


Table  9.— Galesburg  Experiment  Field:  Financial  Statement 
(Value  of  increase  from  three  acres) 


Series  100. . . . 

Series  200 

Series  300 

Years  

Corn 

Oats 

Grass 

1904 

Corn 

Wheat 

Grass 

1905 

Oats 

Clover 

Corn 

1906 

Wheat 

Grass 

Corn 

1907 

Clover 

Corn 

Oats 

1908 

Grass 

Corn 

Wheat 

1909 

Corn 

Oats 

Wheat 

1910 

Corn 

Clover 

Clover 

1911 

Oats 

Wheat 

Corn 

1912 

Aver- 

age 

1907 

to 

1912 

For  residues  . . 
For  manure. . . 
For  phosph’r’s 
For  potassium 
For  nitrogen. . 

$ 1.33 
5.06 
12.93 

$ 3.93 
3.67 
.97 

$2.70 

3.41 

4.00 

$6  77 
.14 
6.31 

$-13.14' 

2.70' 

7.20 

-1.22 

3.98 

$-5.34' 

2.90' 

7.42 

-.13 

3.32 

$ 1.132 
3.578 
4.85 
2.00 
-.90 

$-23 . 46 
5.252 
6.14 
4.13 
.31 

$ -.16 
8.16 
11.49 
1.06 
-4.12 

$7.31 

1.00 

1.48 

'One  crop  only. 
!Two  crops  only. 


In  Table  9 is  given  a financial  summary  of  the  results  thus  far  secured 
from  the  Galesburg  field.  Three  facts  are  clearly  brought  out  by  the  data : 

First. — Commercial  nitrogen  at  15  cents  a pound  has  never  paid  its  cost, 
and  as  the  system  of  providing  “home-grown”  nitrogen  in  crop  residues  has 
developed,  the  effect  of  commercial  nitrogen  has  decreased,  so  that  as  an 
average  of  the  last  five  years  it  has  paid  back  only  4 percent  of  its  annual 
cost. 

Second. — Potassium,  likewise,  has  never  paid  its  cost,  but  during  the 
early  years,  when  no  adequate  provision  was  made  for  decaying  organic 
matter,  the  soluble  potassium  salt  produced  a very  marked  effect,  due  in  part, 
no  doubt,  to  the  fact  that  it  helped  to  dissolve  and  make  available  the  raw 
phosphate  always  applied  with  it.  With  the  subsequent  increase  in  decaying 
organic  matter,  the  effect  of  potassium  has  been  greatly  reduced.  As  an 
average  of  the  last  six  years,  potassium  costing  $7.50  has  paid  back  only  $1. 

Third.- — Phosphorus  applied  in  fine-ground  natural  rock  phosphate  in 
part  as  top-dressing,  and  with  no  adequate  provision  for  decaying  organic 
matter,  paid  only  47  percent  on  the  investment  as  an  average  of  the  first 
three  years.  But  it  should  be  kept  in  mind  that  the  word  investment  is  here 
used  in  its  proper  sense,  for  the  phosphorus  that  was  removed  in  the  in- 
crease produced  was  less  than  2 percent  of  the  amount  applied,  and  that  re- 
moved in  the  total  crops,  less  than  one-third.  During  the  last  six  years, 
however,  the  phosphorus  has  paid  130  percent  on  the  investment,  even  tho 
two-thirds  of  the  application  remains  to  positively  enrich  the  soil. 


20 


Soil  Report  No.  7 


[September, 


The  results  from  the  Galesburg  experiment  field  furnish  some  interest- 
ing and  valuable  illustrations  of  the  danger  of  drawing  incorrect  conclusions 
from  field-culture  experiments  conducted  for  a short  time  only  and  without 
comprehensive  knowledge  of  the  factors  involved.  Thus,  the  first  year  the 
effect  of  potassium  ($5.06)  was  four  times,  and  that  of  nitrogen  ($12.93) 
ten  times  as  great  as  the  effect  of  phosphorus  ($1.33) ; whereas  in  the  last 
year  the  effect  of  phosphorus  ($11.49)  was  eleven  times  that  of  potassium 
($1.06),  while  commercial  nitrogen  applied  in  addition  to  the  crop  residues 
appears  to  have  been  detrimental.  These  facts  only  support  the  following 
statement  quoted  on  page  208  of  Bulletin  123,  “The  Fertility  in  Illinois  Soils” : 

“In  considering  the  general  subject  of  culture  experiments  for  determining 
fertilizer  needs,  emphasis  must  be  laid  on  the  fact  that  such  experiments  should 
never  be  accepted  as  the  sole  guide  in  determining  future  agricultural  practice. 
If  the  culture  experiments  and  the  ultimate  chemical  analysis  of  the  soil  agree 
in  the  deficiency  of  any  plant-food  element,  then  the  information  is  conclusive 
and  final;  but  if  these  two  sources  of  information  disagree,  then  the  culture 
experiments  should  be  considered  as  tentative  and  likely  to  give  way  with 
increasing  knowledge  and  improved  methods  to  the  information  based  on  chem- 
ical analysis,  which  is  absolute.”1 

The  Subsurface  and  Subsoil 

In  Tables  10  and  11  are  recorded  the  amounts  of  plant  food  in  the  sub- 
surface and  the  subsoil  strata  of  the  McDonough  county  soils,  but  it  should 
be  remembered  that  these  supplies  are  of  little  value  unless  the  top  soil  is 
kept  rich.  Probably  the  most  important  information  contained  in  these  tables 
is  that  the  upland  timber  soils  are  usually  more  strongly  acid  in  the  sub- 
surface and  the  subsoil  than  in  the  surface.  This  emphasizes  the  importance 
of  having  plenty  of  limestone  in  the  surface  soil  to  neutralize  the  acid  mois- 
ture that  rises  from  the  lower  strata  by  capillary  action  during  times  of 
partial  drouth,  which  are  critical  periods  in  the  life  of  such  plants  as  clover. 
Thus,  while  the  common  brown  silt  loam  prairie  soil  is  practically  neutral, 
the  upland  timber  soil  of  similar  topography  is  already  in  need  of  limestone ; 
and,  as  already  explained,  it  is  much  more  deficient  in  phosphorus  and  nitro- 
gen than  is  the  common  prairie  soil. 

'Taken  from  “Culture  Experiments  for  Determining  Fertilizer  Needs,”  by  C.  G.  H. 
in"Cyclopedia  of  American  Agriculture,  Volume  I,  page  475. 


McDonough  County 


21 


1913] 


Table  10.— Fertility  in  the  Soils  of  McDonough  County 
Average  pounds  per  acre  in  4 million  pounds  of  subsurface  soil  (about  6%  to  20  inches) 


Soil 

type 

No. 

Soil  type 

Total 

organic 

carbon 

Total 

nitro- 

gen 

Total 

phos- 

phorus 

Total 

potas- 

sium 

Total 

magne- 

sium 

Total 

cal- 

cium 

Lime-  Lame- 
stone  stone 
present  requir'd 

Upland  Prairie  Soils 

526 

Brown  silt  loam 

68  172 

5 896 

1 956 

67  664 

22  968 

21  464 

200 

520 

Black  clay  loam 

93  120 

7 467 

2 693 

59  987 

26  133 

35  413 

40 

528 

Brown-gray  silt 

loam  on  tight 

clay 

45  320 

3 920 

1 600 

65  000 

17  440 

IS  880 

160 

525.1 

Black  silt  loam 

on  clay 

68  080 

5 480 

1 880 

62  920 

25  840 

28  400 

80 

Upland  Timber  Soils 


Yellow-gray  silt 
loam  . 

17  510 

2 150 

1 420 

72  720 

20  200 

15  090 

750 

Y ellow  silt  loam 

13  520 

1 960 

1 700 

75  620 

23  640 

14  640 

2 190 

Light  gray  silt 
loam  on  tight 
clay 

9 680 

1 680 

1 680 

72  840 

21  280 

14  000 

6 880 

Swamp  and  Bottom-Land  Soils 


1326  1 Deep  brown  silt 

1 

I loam. . .... 

58  920  | 6 040 

3 040  I 74  840  | 19  080 

20  240  | 

80 

Table  11. — Fertility  of  the  Soils  of  McDonough  County 


Average  pounds  per  acre  in  6 million  pounds  of  subsoil  (about  20  to  40  inches) 


Soil 

Total 

Total 

Total 

Total 

Total 

Total 

calcium 

Lime- 

Lime- 

type 

Soil  type 

organic 

nitro- 

phos- 

potas- 

magne- 

stone 

stone 

No. 

carbon 

gen 

phorus 

sium 

sium 

present 

requir’d 

Upland  Prairie  Soils 


526 

Brown  silt  loam 

38  430 

4 056 

2 520 

99  246 

47  874 

34  284 

432 

520 

Black  clay  loam 

45  660 

3 580 

3 360 

93  560 

45  100 

47  600 

4 240 

528 

Brown-gray  silt 

loam  on  tight 

clay 

32  160 

3 480 

2 460 

91  500 

42  180 

30  060 

240 

525.1 

Black  silt  loam 

on  clay 

16  560 

2 700 

2 520 

97  380 

46  380 

40  740 

60 

Upland  Timber  Soils 

534 

Y ellow-gray  silt 

loam 

16  590 

2 550 

2 520 

105  090 

39  630 

21  465 

6 495 

535 

Yellow  silt  loam 

4 860 

2 130 

3 030 

114  300 

41  640 

27  000 

3 750 

532 

Light  gray  silt 

loam  on  tight 

clay 

5 160 

2 520 

2 940 

106  860 

44  940 

25  740 

4 620 

Swamp  and  Bottom-Land  Soils 


1326 

Deep  brown  silt 

loam 

25  260 

2 940 

4 620 

108  780 

27  360 

18  780 

16  800 

22 


Soil  Report  No.  7 


[September, 


INDIVIDUAL  SOIL  TYPES 
(a)  Upland  Prairie  Soils 

The  upland  prairie  soils  of  McDonough  county  comprize  374  square 
miles,  or  65  percent  of  the  entire  area  of  the  county.  They  are  usually  dark 
in  color  owing  to  their  large  organic-matter  content. 

The  accumulation  of  organic  matter  in  the  prairie  soils  is  due  to  the  growth 
of  prairie  grasses  that  once  covered  them,  and  whose  network  of  roots  has 
been  protected  from  complete  decay  by  .the  imperfect  aeration  afforded  by 
the  covering  of  fine  soil  material  and  the  moisture  it  contains.  On  the  native 
prairies,  the  tops  of  these  grasses  were  usually  burned  or  became  almost  com- 
pletely decayed.  From  a sample  of  virgin  sod  of  “blue  stem,”  one  of  the 
most  common  prairie  grasses,  it  has  been  determined  that  an  acre  of  this 
soil  to  a depth  of  7 inches  contained  13%  tons  °f  roots.  Many  of  these 
roots  died  each  year  and  by  partial  decay  formed  the  humus  of  these  dark 
prairie  soils. 


Brown  Silt  Loam  (526) 

The  brown  silt  loam  is  the  most  important  as  well  as  the  most  extensive 
type  of  soil  in  McDonough  county.  It  covers  an  area  of  318.18  square  miles 
(203,637  acres),  or  55.44  percent  of  the  entire  area  of  the  county. 

This  type  is  generally  sufficiently  rolling  for  fair  natural  surface  drain- 
age, altho  there  are  some  exceptions  where  the  land  is  so  flat  as  to  require 
thoro  artificial  drainage.  Draws  or  swales  are  frequently  “seepy.”  To  carry 
off  this  seepage  from  the  higher  land,  there  should  be  at  least  one  line  of  tile, 
and  two  may  sometimes  be  necessary. 

The  surface  soil,  o to  6^3  inches,  is  a brown  silt  loam  varying  from  a 
yellowish  brown  on  the  more  rolling  areas  to  a dark  brown  or  black  on  the 
more  nearly  level  and  poorly-drained  areas.  In  physical  composition  it  varies  to 
some  extent,  but  it  normally  contains  70  to  80  percent  of  the  different  grades 
of  silt.  The  clay  content,  usually  10  to  12  percent,  increases  as  the  type 
approaches  black  clay  loam  (520)  and  black  silt  loam  on  clay  (525.1),  nat- 
urally becoming  greater  in  the  poorly-drained  areas.  The  sand  content  varies 
from  8 to  20  percent  and  is  usually  of  the  finer  grades.  The  organic-matter 
varies  from  3 to  5 percent,  averaging  4.2  percent,  or  42  tons  per  acre.  Where 
this  type  passes  into  the  brown-gray  silt  loam  on  tight  clay  (528)  or  the 
yellow-gray  silt  loam  (534),  the  amount  of  organic  matter  becomes  lower. 
The  forest  trees  that  once  grew  on  the  upland  in  this  climate  reduced  the  or- 
ganic matter  and  ultimately  changed  the  original  brown  prairie  soil  into  yellow- 
gray  silt  loam.  These  forests  consisted  quite  largely  of  black  walnut,  with 
such  other  trees  as  wild  cherry,  hackberry,  ash,  and  elm.  A black-walnut 
soil  is  generally  recognized  by  farmers  as  being  one  of  the  best  timber  soils. 
It  still  contains,  as  a rule,  a large  amount  of  the  organic  matter  that  accumu- 
lated from  the  prairie  grasses. 

The  subsurface  is  represented  by  a stratum  varying  from  5 to  14  inches 
in  thickness.  This  variation  is  due  to  changing  topography,  the  stratum  be- 
ing thinner  on  the  more  rolling  areas  and  thicker  on  the  level  areas.  In  phy- 
sical composition  the  subsurface  varies  the  same  as  the  surface  soil,  but  it 
usually  contains  a slightly  larger  amount  of  clay  and  a much  smaller  amount 
of  organic  matter.  In  some  places,  it  may  become  quite  heavy,  as  where  the 
brown  silt  loam  grades  toward  the  black  silt  loam  on  clay  (525.1).  In  color 


1M3\ 


McDonough  County 


23 


the  subsurface  varies  from  a dark  brown  or  almost  black  to  a light  or  a yel- 
lowish brown.  It  usually  becomes  lighter  with  depth  and  passes  into  the 
yellow  subsoil. 

The  natural  subsoil  begins  12  to  21  inches  beneath  the  surface  and  ex- 
tends to  an  indefinite  depth,  but  it  is  usually  sampled  to  a depth  of  40  inches. 
It  varies  from  a yellow  to  a drabbish  yellow,  clayey  silt.  In  the  level  or 
nearly  level  areas,  it  is  of  a drab  color,  while  in  the  more  rolling  areas,  where 
better  drainage  has  allowed  higher  oxidation  of  the  iron  to  take  place,  it  is 
of  a yellow  or  brownish  yellow  color.  The  upper  part  of  the  subsoil  usually 
contains  more  clay  than  the  lower  part. 

The  subsoil  is  usually  pervious  to  water,  permitting  good  drainage,  but 
where  this  type  grades  toward  brown-gray  silt  loam  on  tight  clay  (528),  a 
phase  is  found  that  is  rather  hard  to  drain. 

While  this  type  is  in  fair  physical  condition,  yet  continuous  cropping  to 
corn,  or  corn  and  oats,  with  the  burning  of  the  stalks,  is  destroying  the  tilth ; 
the  soil  is  becoming  more  difficult  to  work;  it  runs  together  more;  and 
aeration,  granulation,  and  absorption  of  moisture  do  not  take  place  as  readily 
as  formerly.  This  condition  of  poor  tilth  may  become  serious  if  the  present 
methods  of  management  continue;  it  is  already  one  of  the  factors  that  limit 
the  crop  yields.  The  remedy  is  to  increase  the  organic-matter  content  by 
plowing  under  crop  residues,  such  as  corn  stalks,  straw,  and  clover,  instead 
of  selling  them  from  the  farm  or  burning  them,  as  is  so  often  practiced  at 
present.  Where  corn  follows  corn,  the  stalks  should  be  thorolv  cut  up  with 
a sharp  disk  or  stalk  cutter,  and  turned  under.  Likewise,  the  straw  should 
be  returned  to  the  land  in  some  practical  way,  either  directly  or  in  manure. 
Clover  should  be  one  of  the  crops  grown  in  the  rotation,  and  it  should  be 
plowed  under  directly  or  in  manure  instead  of  being  sold  as  hay,  except  when 
manure  can  be  brought  back. 

The  addition  of  fresh  organic  matter  is  not  only  of  great  value  in  im- 
proving the  physical  condition  of  this  type  of  soil,  but  it  is  of  even  greater 
importance  because  of  its  nitrogen  content  and  because  of  its  power,  as  it 
■decays,  to  liberate  potassium  from  the  inexhaustible  supply  in  the  soil,  and 
phosphorus  from  the  phosphate  contained  in  or  applied  to  the  soil. 

For  permanent  profitable  systems  of  farming  on  brown  silt  loam,  phos- 
phorus should  be  applied  liberally,  and  sufficient  organic  matter  should  be 
provided  to  furnish  the  necessary  amount  of  nitrogen.  On  the  ordinary  type, 
limestone  is  already  becoming  deficient.  In  live-stock  farming  an  application 
of  two  tons  of  limestone  and  one-half  ton  of  fine-ground  rock  phosphate  per 
acre  every  four  years,  with  the  return  to  the  soil  of  all  manure  made  from  a 
rotation  of  corn,  corn,  oats,  and  clover,  will  maintain  the  fertility  of  this 
type,  altho  heavier  applications  of  phosphate  may  well  be  made  during  the 
first  two  or  three  rotations.  If  grain  farming  is  practiced,  the  rotation  may 
be  wheat,  corn,  oats,  and  clover,  with  an  extra  seeding  of  clover  as  a cover 
crop  in  the  wheat,  to  be  plowed  under  late  in  the  fall  or  in  the  following 
spring  for  corn;  and  most  of  the  crop  residues,  with  all  clover  except  the 
seed,  should  also  be  plowed  under.  In  either  system,  alfalfa  may  be  grown  on 
a fifth  field  and  moved  every  five  years,  the  hay  being  fed  or  sold.  (For  re- 
sults of  field  experiment  on  the  brown  silt  loam  prairie,  see  Tables  3 to  9.) 


24 


Soil  Eepoet  No.  7 


[. September , 


Black  Clay  Loam  (520) 

The  black  clay  loam  represents  in  part  the  originally  swampy  and  poorly- 
drained  land  (the  flat  prairie)  of  the  upper  Illinois  glaciation.  It  is  frequently 
called  “gumbo”  because  of  its  sticky  character.  Its  formation  in  the  low 
places  is  due  to  the  accumulation  of  organic  matter  and  the  washing  in  of  clay 
and  fine  silt  from  the  slightly  higher  adjoining  lands.  This  type  in  McDon- 
ough county  covers  19.22  square  miles  (12,301  acres),  or  3.35  percent  of  the 
total  area  of  the  county.  In  topography  it  is  so  flat  that  in  the  large  areas 
the  problem  of  getting  a sufficient  outlet  for  drainage  has  caused  some  dif- 
ficulty. 

The  surface  stratum  is  a black,  granular,  clay  loam  with  an  average  or- 
ganic-matter content  of  6.75  percent,  or  67  tons  per  acre,  the  amount  varying 
from  60  to  80  tons.  The  more  luxuriant  growth  of  prairie  grasses  that  once 
covered  this  black  clay  loam,  and  the  preservation  of  their  roots  by  the  moist 
condition  of  the  soil,  has  resulted  in  a greater  accumulation  of  organic  matter 
in  this  type  than  in  the  more  rolling  types  of  upland  prairie  soils. 

The  surface  soil  is  naturally  quite  granular.  This  property  of  granula- 
tion is  important  to  all  soils,  but  especially  so  to  heavy  ones,  for  by  it  the 
soil  is  kept  in  good  tilth  and  rendered  pervious  to  air  and  water.  If  the 
granules  are  destroyed  by  puddling  (as  they  are  if  the  soil  is  worked  or  stock 
are  allowed  to  trample  on  it  while  it  is  wet),  they  will  be  formed  again  by 
freezing  and  thawing  or  by  moisture  changes  (wetting  and  drying).  These 
natural  agencies  produce  “slaking,”  as  the  process  is  usually  termed.  If, 
however,  the  organic-matter  or  the  lime  content  becomes  low,  this  tendency 
to  granulate  grows  less  and  the  soil  becomes  more  difficult  to  work. 

The  subsurface  extends  to  a depth  of  10  to  16  inches  below  the  surface 
stratum.  It  differs  from  the  surface  in  color,  becoming  lighter  with  depth, 
the  lower  part  of  the  stratum  passing  into  a drab  or  yellowish,  silty  clay.  It 
is  quite  pervious  to  water,  owing  to  the  jointing  or  checking  produced  by 
shrinkage  in  times  of  drouth.  The  amount  of  organic  matter  varies  from 
3.8  to  4.6  percent. 

The  subsoil  is  usually  a drab  or  dull  yellow,  silty  clay,  but  locally  it  may 
be  a yellow,  clayey  silt  or  even  a silt.  As  a rule,  the  iron  is  not  highly  ox- 
idized, because  of  poor  drainage.  The  checking  and  jointing  in  the  subsoil 
make  it  readily  permeable  to  water  and  consequently  easy  to  drain.  In  some 
areas  the  subsoil  contains  large  numbers  of  limestone  concretions  (calcium 
carbonate). 

Black  clay  loam  presents  many  variations.  Here,  as  elsewhere,  the  bound- 
ary lines  between  different  soil  types  are  not  always  distinct,  but  types  fre- 
quently pass  from  one  to  another  very  gradually,  thus  giving  an  interme- 
diate zone  of  greater  or  less  width.  Variations  between  black  clay  loam 
(520)  and  brown  silt  loam  (526)  are  very  likely  to  occur  since  they  are 
usually  adjoining  types.  This  gives  a lighter  phase  of  black  clay  loam  (520), 
with  a smaller  organic-matter  content  than  the  average,  or  a heavier  phase  of 
brown  silt  loam  (526),  darker,  and  with  a larger  amount  of  organic  matter 
than  the  average.  (In  chemical  composition,  the  gradation  zone  is  inter- 
mediate between  the  two  normal,  adjoining  types.)  Again,  in  some  areas  of 
black  clay  loam  there  has  been  enough  silty  material  washed  in  from  the 
surrounding  higher  lands,  especially  near  the  edges  of  the  areas,  to  modify 
the  character  of  the  surface  soil.  This  change  is  taking  place  more  rapidly 
now,  with  the  annual  cultivation  of  the  soil,  than  formerly,  when  washing 
was  largely  prevented  by  prairie  grasses. 


1913] 


McDonough  County 


25 


Drainage  is  the  first  requirement  of  this  type.  Altho  it  usually  has  but 
little  slope,  yet  because  of  its  perviousness  it  affords  a good  chance  for  tile 
drainage.  Keeping  the  soil  in  good  physical  condition  is  very  essential,  and 
thoro  drainage  helps  to  do  this  to  a great  extent.  As  the  organic  matter  is 
destroyed  by  cultivation  and  nitrification  and  the  lime  removed  by  cropping 
and  leaching,  the  physical  condition  of  the  soil  becomes  poorer,  and  conse- 
quently it  becomes  more  difficult  to  work.  Both  the  organic  matter  and  the 
lime  tend  naturally  to  develop  a granular  condition,  but  they  are  especially 
effective  when  aided  by  careful  and  well-timed  cultivation.  The  organic 
matter  should  be  maintained  by  turning  under  manure,  clover,  and  crop 
residues,  such  as  corn  stalks  and  straw.  Too  often  the  crop  residues  are  burned 
or  put  back  in  such  a way  as  not  to  produce  the  greatest  benefit.  Straw  is  too 
frequently  left  in  lots  until  the  larger  part  of  the  organic  matter  is  lost  by 
fermentation  and  leaching.  Ground  limestone  applied  liberally  when  the  soil 
becomes  acid,  will  also  help  to  keep  the  soil  in  good  physical  condition. 

While  black  clay  loam  is  one  of  the  best  soils  in  the  state,  the  clay  and 
humus  contained  in  it  give  it  the  property  of  shrinkage  and  expansion  to  such 
a degree  as  to  be  somewhat  objectionable  at  times.  When  the  soil  is  wet, 
these  constituents  expand,  and  when  the  moisture  evaporates  or  is  used  by 
crops,  they  shrink.  This  results  in  the  formation  of  cracks  up  to  two  inches 
or  more  in  width  and  extending  with  lessening  width  to  a foot  or  more  in 
depth.  These  cracks  allow  the  soil  strata  to  dry  out  rapidly,  and  as  a result, 
the  crop  is  injured  thru  lack  of  moisture.  They  may  also  do  considerable 
damage  by  “blocking  out”  hills  of  corn  and  severing  the  roots.  While  crack- 
ing may  not  be  prevented  entirely,  yet  good  tilth,  with  a soil  mulch,  will  do 
much  toward  that  end. 

This  type  is  fairly  well  supplied  with  plant  food,  which  is  usually  liber- 
ated with  sufficient  rapidity  by  a good  rotation  and  by  the  addition  of  mod- 
erate amounts  of  organic  matter.  The  amount  of  organic  matter  added  must 
be  increased,  of  course,  with  continued  farming,  until  the  nitrogen  supplied 
is  equal  to  that  removed.  Altho  the  addition  of  phosphorus  is  not  expected 
to  produce  marked  profit,  it  is  likely  to  pay  its  cost  in  the  second  or  third 
rotation,  and  even  by  maintaining  the  productive  power  of  the  land,  the 
capital  invested  is  protected. 

This  type  is  rich  in  magnesium  and  calcium,  and  the  subsoil  usually  con- 
tains plenty  of  carbonates.  With  continued  cropping  and  leaching,  applica- 
tions of  limestone  will  be  needed.  (No  field  experiments  have  been  conducted 
as  yet  on  this  type  of  soil.) 

Brown-Gray  Silt  Loam  on  Tight  Clay  (528) 

Brown-gray  silt  loam  on  tight  clay  is  found  principally  in  the  southwest 
part  of  McDonough  county.  It  comprizes  29.25  square  miles  (18,720  acres), 
or  5.1  percent  of  the  total  area. 

The  surface  soil,  o to  6%  inches,  is  a brown  or  grayish  brown  silt  loam 
containing  some  fine  sand  and  coarse  silt,  which  give  it  a fine  texture.  The 
organic-matter  content  varies  somewhat  according  to  the  relation  of  the  type 
to  other  types,  being  greater  where  it  approaches  brown  silt  loam  (526)  or 
black  silt  loam  on  clay  (525.1),  and  less  where  it  grades  toward  yellow-gray 
silt  loam  (534) ; the  average  is  about  3.5  percent. 

The  subsurface  is  represented  by  a stratum  10  to  12  inches  thick.  In 
color  it  varies  from  a brown  to  a gray  or  grayish  brown,  the  upper  part  of 


26 


moil  Report  No.  7 


[September, 


the  stratum  usually  being  brown,  and  the  lower  part,  gray  or  grayish  brown. 
It  differs  from  the  surface  stratum  principally  in  the  amount  of  organic 
matter  it  contains. 

The  natural  subsoil  consists  of  a stratum  of  tight  clay  beginning  16  to 
18  inches  beneath  the  surface  and  varying  in  thickness  from  io  to  20  inches. 
It  is  usually  underlain  by  a pervious  silt. 

This  type  is  rather  flat,  and  much  of  it  needs  drainage.  Owing  to  the 
impervious  character  of  the  subsoil,  it  is  in  greater  need  of  tile  drainage 
than  is  the  brown  silt  loam,  and  the  lines  of  tile  should  be  placed  nearer  each 
other.  For  efficient  drainage,  they  should  not  be  over  5 rods  apart,  and  3 or 
4 rods  is  better.  Care  should  be  taken  to  increase  the  amount  of  organic 
matter  by  the  proper  rotation  6f  crops,  by  turning  under  crop  residues,  and 
by  the  application  of  farm  manure.  Deep-rooting  crops,  such  as  red,  mam- 
moth, or  sweet  clover,  should  be  grown  in  order  to  loosen  up,  in  a measure, 
the  tight  clay  subsoil  and  promote  drainage  and  aeration. 

From  Table  2 it  will  be  seen  that  the  surface  soil  contains  only  900 
pounds  of  phosphorus  per  acre.  To  increase  the  amount  of  this  element,  lib- 
eral applications  of  fine-ground  rock  phosphate  should  be  made  in  connection 
with  the  decaying  organic  matter,  as  on  the  brown  silt  loam.  Limestone 
should  be  applied  at  the  rate  of  2 to  3 tons  per  acre  every  four  to  six  years. 
The  initial  application  may  well  be  1 ton  of  phosphate  and  4 tons  of  limestone. 

On  recently  established  twenty-acre  experiment  fields  on  this  type  of  soil 
at  Carthage  in  Hancock  county  and  at  Clayton  in  Adams  county,  organic 
manures  increased  the  yield  of  corn,  in  the  very  dry  season  of  1912,  from 
30.6  to  40.5  bushels  at  Carthage  and  from  36.8  to  46.7  bushels  at  Clayton. 
Where  both  organic  manures  and  rock  phosphate  were  applied,  the  average 
yield  on  the  Carthage  field  was  increased  to  48.1  bushels  and  on  the  Clayton 
field  to  55.6  bushels.  Thus  it  is  seen  that  the  average  increase  in  the  corn 
yield  resulting  from  the  use  of  organic  manures  was  9.9  bushels  per  acre, 
and  from  the  use  of  organic  manures  reinforced  with  rock  phosphate,  18.2 
bushels.  Limestone  applied  subsequently  is  showing  marked  benefit  in  1913 
at  both  Carthage  and  Clayton,  especially  on  the  growth  of  sweet  clover, 
which  is  used  as  a green-manure  cover  crop.  Thus  the  data  already  secured 
are  in  agreement  with  the  analytical  data  for  this  soil  type. 


Black  Silt  Loam  on  Clay  (525.1) 

Black  silt  loam  on  clay  comprizes  7.24  square  miles  (4,634  acres),  or  1.26 
percent  of  the  area  of  McDonough  county.  It  occurs  mostly  in  small  areas 
over  the  county,  often  in  proximity  to  the  brown-gray  silt  loam  on  tight  clay 
(528).  In  topography  it  is  usually  about  the  same  as  the  black  clay  loam 
(520),  but  it  does  not  permit  of  as  good  underdrainage  because  of  the  some- 
what tight  character  of  the  subsoil.  This  is  especially  true  where  it  ap- 
proaches the  brown-gray  silt  loam  on  tight  clay  (528). 

The  surface  soil,  o to  6^3  inches,  is  a black  silt  loam,  varying  on  the  one 
hand  toward  black  clay  loam  (520),  and  on  the  other  to  brown  silt  loam 
(526)  or  brown-gray  silt  loam  on  tight  clay  (528).  When  thoroly  drained, 
it  is  naturally  granular  and  of  good  tilth,  but  the  same  precautions  must  be 
taken  to  keep  it  in  good  physical  condition  as  are  necessary  with  black  clay 
loam  (520).  The  organic-matter  content  averages  about  5.5  percent,  or  55 
tons  per  acre. 


1913] 


McDonough  County 


The  subsurface  stratum  varies  from  8 to  14  inches  in  thickness.  In  color 
it  varies  from  black  to  dark  brown  near  the  top  of  the  stratum,  to  drab  or 
yellowish  drab  near  the  bottom.  The  proportion  of  clay  increases  with  depth. 

The  subsoil  resembles  that  of  the  black  clay  loam  (520)  except  that  it 
is  heavier. 

Drainage  is  one  of  the  first  requirements  of  this  type. 

For  maintaining  good  tilth  one  of  the  most  practical  means  is  the  incor- 
poration of  organic  matter.  This  can  be  accomplished  by  providing  a proper 
rotation  of  crops  (which  should  include  clover  or  some  other  legume),  and 
turning  under  the  legume,  together  with  the  crop  residues  (corn  stalks  and 
straw).  Such  organic  matter  or  farm  manure  will  not  only  help  in  maintain- 
ing good  tilth  but  it  will  also  supply  the 'amount  of  nitrogen  required  in  per- 
manent economic  systems  of  general  farming. 

In  phosphorus  content,  black  silt  loam  on  clay  lies  between  the  brown 
silt  loam  and  the  brown-gray  silt  loam  on  tight  clay.  Fine-ground  rock 
phosphate  should  be  applied  in  connection  with  the  organic  manures  at  the 
rate  of  about  one-half  ton  per  acre  every  four  years.  The  initial  application 
may  well  be  one  ton  or  more. 

This  type  of  soil  is  practically  neutral,  which  means  that  it  is  not  dis- 
tinctly acid  and  yet  that  it  contains  no  limestone.  For  the  best  results,  es- 
pecially in  the  growing  of  legume  crops,  limestone  should  be  applied.  Two 
tons  per  acre  every  four  or  five  years  will  maintain  a sufficient  supply  in  the 
soil. 


(b)  Upland  Timber  Soils 

In  the  soils  of  the  upland  forests,  there  is  found  no  such  quantity  of  roots 
as  is  found  in  the  prairie  soils.  The  vegetable  material  consists  of  leaves  and 
twigs  which  fall  upon  the  surface  and  either  are  burned  by  forest  fires  or  un- 
dergo almost  complete  decay.  There  is  very  little  chance  for  these  to  become 
mixed  with  the  soil.  As  a result,  the  organic-matter  content  of  the  upland 
timber  soils  has  been  lowered  until  in  some  parts  of  the  state  a low  condi- 
tion of  apparent  equilibrium  has  been  reached. 

Yellow-Gray  Silt  Loam  (534) 

Yellow-gray  silt  loam  in  McDonough  county  occurs  in  the  outer  timber 
belts  along  the  streams,  and  covers  39  square  miles  (24,960  acres),  or  6.79 
percent  of  the  county.  In  topography  it  is  sufficiently  rolling  for  good  sur- 
face drainage  and  without  much  tendency  to  wash  if  proper  care  is  taken. 

The  surface  soil,  o to  6^3  inches,  is  a gray  to  yellowish  gray  silt  loam, 
incoherent  and  mealy  but  not  granular.  The  amount  of  organic  matter  con- 
tained in  it  varies  from  1.8  to  3.4  percent  with  an  average  of  2.3  percent  or 
23  tons  per  acre.  This  variation  is  due  to  the  relation  of  the  type  to  other 
types,  the  content  of  organic  matter  increasing  where  it  grades  into  brown 
silt  loam  (526)  and  brown-gray  silt  loam  on  tight  clay  (528),  and  decreasing 
where  it  passes  into  yellow  silt  loam  (535)  and  light  gray  silt  loam  on  tight 
clay  (532).  In  some  places,  erosion  has  reduced  the  amount  of  organic 
matter. 

The  subsurface  stratum  varies  from  3 to  10  inches  in  thickness,  erosion 
having  reduced  its  depth  on  the  more  rolling  areas.  In  color  it  is  a gray, 
grayish  yellow,  or  yellow  silt  loam,  somewhat  pulverulent,  but  becoming  more 
coherent  and  plastic  with  depth. 


28 


Soil  Eepoet  No.  7 


[September, 


The  subsoil  is  a yellow  or  grayish  yellow,  clayey  silt  or  silty  clay,  some- 
what plastic  when  wet,  but  friable  when  only  moist,  and  pervious  to  water. 

In  the  management  of  this  yellow-gray  silt  loam,  one  of  the  most  es- 
sential points  is  the  maintenance  or  increase  of  organic  matter.  This  is  nec- 
essary in  order  to  supply  nitrogen  and  liberate  mineral  plant  food,  to  give 
better  tilth,  to  prevent  “running  together,”  and,  on  some  of  the  more  rolling 
phases,  to  prevent  washing.  Another  essential  is  the  neutralization  of  the 
acidity  of  the  soil  by  the  application  of  ground  limestone,  so  that  clover, 
alfalfa,  and  other  legumes  may  be  grown  more  successfully.  The  initial  ap- 
plication may  well  be  4 or  5 tons  per  acre,  after  which  2 tons  per  acre  every 
four  or  five  years  will  be  sufficient.  Since  the  soil  is  poor  in  phosphorus, 
this  element  should  be  applied,  preferably  in  connection  with  farm  manure 
or  clover  plowed  under.  In  permanent  systems  of  farming,  fine-ground  nat- 
ural rock  phosphate  will  be  found  the  most  economical  form  in  which  to  sup- 
ply the  phosphorus. 

For  definite  results  from  the  most  practical  field  experiments  upon  typical 
vellow-gray  silt  loam,  we  must  go  down  into  “Egypt,”  where  the  people  of 
Saline  county,  especially  those  in  the  vicinity  of  Raleigh  and  Galatia,  have 
provided  the  University  with  a very  suitable  tract  of  this  type  of  soil  for  a 
permanent  experiment  field.  There,  as  an  average  of  triplicate  tests  each  year, 
the  yield  of  corn  on  untreated  land  was  25.3  bushels  in  1910,  23.6  bushels  in 
1911,  and  22  bushels  in  1912;  while  on  duplicate  plots  treated  with  heavy 
applications  of  limestone  and  a limited  amount  of  organic  manures,  the  cor- 
responding yields  were  41.4  bushels  in  1910,  41.3  bushels  in  1911,  and  50.1 
bushels  in  1912,  the  corn  being  grown  on  a different  series  of  plots  every 
year  in  a four-year  rotation  of  wheat,  corn,  oats,  and  clover.  About  the 
same  proportionate  increases  were  produced  in  wheat  and  hay,  and  the  effect 
on  oats  was  also  marked.  Owing  to  the  low  supply  of  organic  matter,  phos- 
phorus produced  no  benefit,  as  an  average,  during  the  first  two  years;  but 
with  increasing  applications  of  organic  matter,  the  effect  of  phosphorus  is 
seen  in  the  crops  of  1912  and  1913.  Of  course  a single  four-year  rotation 
cannot  be  practiced  in  less  than  four  years,  and  the  full  benefit  of  a system 
of  rotation  and  soil  treatment  is  not  to  be  expected  before  the  third  or  fourth 
four-year  period. 

While  limestone  is  the  material  first  needed  for  the  economic  improve- 
ment of  the  more  acid  soils  of  southern  Illinois,  with  organic  manures  and 
phosphorus  to  follow  in  order,  the  less  acid  soils  of  the  west-central  part  of 
the  state  are  first  in  need  of  phosphorus,  in  which  they  are  relatively  about  as 
deficient  as  the  acid  soils  are  in  lime.  Organic  matter  is  also  greatly  needed  by 
these  less  acid  soils. 

Table  12  shows  in  detail  eleven  years’  results  secured  from  the  Antioch 
soil  experiment  field  located  in  Lake  county  on  the  yellow-gray  silt  loam  of 
the  late  Wisconsin  glaciation.  In  acidity,  this  type  in  McDonough  county  is 
intermediate  between  the  similar  soils  in  Saline  and  Lake  counties,  but  no 
experiment  field  has  been  conducted  on  this  important  soil  type  in  the  upper 
Illinois  glaciation,  in  which  McDonough  county  is  situated. 

The  Antioch  field  was  started  in  order  to  learn  as  quickly  as  possible  just 
what  effect  would  be  produced  by  the  addition  to  this  type  of  soil,  of  nitrogen, 
phosphorus,  and  potassium,  singly  and  in  combination.  These  elements  have 
all  been  added  in  commercial  form.  Only  a small  amount  of  lime  was  ap- 
plied at  the  beginning;  and  with  the  abnormality  of  Plot  101,  and  with  an 
abundance  of  limestone  in  the  subsoil  (a  common  condition  in  the  late  Wis- 


191S ] 


McDt  -jouqh  County 


29 


Table  12.— Crop  Yields  in  Soil  Experiments,  Antioch  Field 


Yellow-gray  silt  loam, 
undulating  timber- 
land;  late  Wisconsin 
glaciation 

Corn 

1902 

Corn 

1903 

Oats 

1904 

Wheat 

1905 

Corn 

1906 

Corn 

1907 

Oats 

1908 

Wheat 

1909 

Corn 

1910 

Corn 

1911 

| Oats 
1912 

Plot 

Soil  treatment 
applied 

Bushels  per  acre 

101 

None1 

44.8 

36.6 

17.8 

18.5 

35.9 

12.4 

65.6 

12.2 

5.2 

34.4 

21.3 

102 

Eime 

45.1 

38.9 

12.8 

10.3 

31.5 

9.5 

61.6 

11.7 

3.0 

24.6 

17.5 

103 

Lime,  nitrogen  . . . 

46.3 

40.8 

2.8 

17.8 

37.8 

6.4 

60.3 

13.0 

1.4 

10.4 

24.4 

104 

Time,  phosphorus 

50.1 

53.6 

12.5 

35.8 

57.4 

13.4 

70.9 

23.3 

6.8 

37.4 

49.1 

105 

Eime,  potassium.. 

48.2 

50.2 

9.7 

21.7 

34.9 

12.9 

62.5 

13.5 

4.6 

20.4 

18.8 

106 

Lime,  nitro.,  phos. 

56.6 

62.7 

15.9 

15.2 

59.3 

20.9 

49.1 

33.8 

6.0 

37.0 

46.9 

107 

Lime, nitro. , potas. 

52.1 

54.9 

10.3 

11.8 

39.0 

11.1 

52.6 

21.0 

1.6 

7.0 

16.9 

108 

Lime, phos.,  potas. 

60.7 

66.0 

19.7 

28.7 

59.1 

18.3 

59.4 

26.2 

3.2 

42.2 

35.9 

109 

Lime,  nitro.,  phos. 
potas 

61.2 

69.1 

31.9 

18.0 

65.9 

31.4 

51.9 

30.5 

3.0 

44.2 

31.9 

110 

Nitro. , phos., potas. 

59.7 

71.8 

37.2 

16.3 

66.3 

28.8 

55.9 

34.5 

4.0 

49.0 

38.1 

Average  Increase:  Bushels  per  Acre 


For  nitrogen 

3.0 

4.7 

1.6 

-8.4 

4.8 

3.9 

-10.1 

5.9 

—1.4 

—6.5 

— .3 

For  phosphorus 

9.2 

16.7 

11.1 

9.0 

24.6 

11.0 

-1.4 

13.7 

2.1 

24.6 

21.6 

For  potassium 

6.0 

11.0 

6.9 

.3 

3.2 

5.9 

-3.9 

2.3 

—1.2 

1.1 

—8.6 

For  nitro.,  phos.  over 

phos 

6.5 

9.1 

3.4 

-20.6 

1.9 

7.5 

-21.8 

10.5 

— .8 

— .4 

2.2 

For  phos.,  nitro.  over 

nitro 

10.3 

21.9 

13.1 

-2.6 

21.5 

14.5 

-11.2 

20.8 

4.6 

26.6 

22.5 

For  potas.,  nitro.,  phos. 

over  nitro. , phos 

4.6 

6.4 

16.0 

2.8 

6.6 

10.5 

2.8 

—3.3 

—3.0 

7.2 

-15.0 

Value  of  Crops  per  Acre  in  Eleven  Years 


Plot 

Soil  treatment  applied 

Total  value 
of  eleven 
crops 

Value  of 
increase 

101 

None 

$112.16 

102 

96.38 

£— 15.78 

103 

104 

Lime,  nitrogen 

Lime,  phosphorus  

97.89 

157.67 

—14.27 

45.51 

105 

L/ime,  potassium 

111.86 

— .30 

106 

Lime,  nitrogen,  phosphorus..  

152.75 

40.59 

107 

Lime,  nitrogen,  potassium 

104.89 

—7.27 

108 

Lime,  phosphorus,  potassium 

160.25 

48.09 

109 

Lime,  nitrogen,  phosphorus,  potassium 

164.83 

52.67 

110 

Nitrogen,  phosphorus,  potassium 

172.78 

60.62 

Value  of  Increase  per  Acre  in  Eleven  Years 

Cost  of 
increase 

For  nitrogen 

For  phosphorus 

For  nitrogen  and  phosphorus  over  phosphorus 

For  phosphorus  and  nitrogen  over  nitrogen 

For  potassium,  nitrogen,  and  phosphorus  over  nitrogen  and 
ohosohorus 

$ 1.51 
61.29 
—4.92 
54.86 

12.08 

$165.00 

27.50 

165.00 

27.50 

27.50 

‘Plot  101,  the  check  plot,  is  the  lowest  ground  but  it  is  well  drained  and  is  appre- 
ciably better  land  than  the  rest  of  the  field.  Plot  102  is  a more  trustworthy  check  plot. 


30 


Soil  Repoet  No.  7 


[September, 


consin  glaciation),  no  conclusions  can  be  drawn  regarding  the  effect  of  lime. 

As  an  average  of  44  tests  (4  each  year  for  11  years),  liberal  applications 
of  commercial  nitrogen  have  produced  a slight  decrease  in  crop  values,  phos- 
phorus has  paid  back  200  percent  of  its  cost,  while  each  dollar  invested  in 
potassium  has  brought  back  only  34  cents  ( a net  loss  of  66  percent).  Thus, 
while  the  detailed  data  show  great  variation,  owing  both  to  some  irregularity 
of  soil  and  to  some  very  abnormal  seasons,  with  three  almost  complete  crop 
failures  (1904,  1907,  and  1910),  yet  the  general  summary  strongly  confirms 
the  analytical  data  in  showing  the  need  of  applying  phosphorus  and  the  profit 
from  its  use,  and  the  loss  in  adding  potassium.  In  most  cases  commercial 
nitrogen  damaged  the  small  grains  by  causing  the  crop  to  lodge ; but  in  those 
years  when  a corn  yield  of  40  bushels  or  more  was  secured  by  the  application 
of  phosphorus  either  alone  or  with  potassium,  then  the  addition  of  nitrogen 
produced  an  increase. 

From  a comparison  of  the  results  from  the  Sibley,  Bloomington,  and 
Galesburg  fields  (see  pages  10  to  20),  we  must  conclude  that  better  yields  are 
to  be  secured  by  providing  nitrogen  by  means  of  farm  manure  or  legume 
crops  grown  in  the  rotation  than  by  the  use  of  commercial  nitrogen,  which  is 
evidently  too  readily  available,  causing  too  rapid  growth  and  consequent 
weakness  of  straw ; and  of  course  the  atmosphere  is  the  most  economic  source 
of  nitrogen  where  that  element  is  needed  for  soil  improvement  in  general 
farming.  (See  Appendix  for  detailed  discussion  of  “Permanent  Soil  Im- 
provement.”) 

Yellow  Silt  Loam  (535) 

In  area,  yellow  silt  loam  stands  second  among  the  soil  types  of  McDon- 
ough county,  covering  144.41  square  miles  (92,422  acres),  or  25.16  percent 
of  the  county.  It  occurs  as  the  hilly  and  badly  eroded  land  on  the  inner  tim- 
ber belts  along  the  streams,  usually  only  in  narrow,  irregular  strips,  with 
arms  extending  up  the  small  valleys.  In  topography  it  is  very  rolling  and  in 
most  places  so  badly  broken  that  it  should  not  be  cultivated  because  of  the 
danger  of  injury  from  washing. 

The  surface  soil,  o to  62/s  inches,  is  a yellow  or  yellowish  gray  silt  loam, 
pulverulent  and  mealy.  It  varies  a great  deal,  owing  to  recent  washing.  In 
some  places  the  natural  subsoil  may  be  exposed.  The  organic-matter  con- 
tent is  about  1.9  percent. 

The  typical  subsurface  varies  in  thickness  from  o to  12  inches,  the  varia- 
tion being  due  to  the  removal  of  all  or  part  of  the  surface  and  subsurface. 

The  subsoil  is  a compact,  yellow,  clayey  silt. 

In  the  management  of  this  yellow  silt  loam,  the  most  important  thing  is 
to  prevent  general  surface  washing  and  gullying.  If  the  land  is  cropped  at 
all,  a rotation  should  be  practiced  that  will  require  a cultivated  crop  as  little 
as  possible  and  allow  pasture  and  meadow  most  of  the  time.  If  tilled,  the 
land  should  be  plowed  deeply;  and  contours  should  be  followed  as  nearly 
as  possible  in  plowing,  planting,  and  cultivating.  Furrows  should  not  be  made 
up  and  down  the  slopes.  Every  means  should  be  employed  to  maintain  and  in- 
crease the  organic-matter  content;  this  will  help  hold  the  soil  and  keep  it 
in  good  physical  condition  so  that  it  will  absorb  a large  amount  of  water 
and  thus  diminish  the  run-off.  (See  Circular  119,  “Washing  of  Soils  and 
Methods  of  Prevention.”) 

Additional  treatment  recommended  for  this  yellow  silt  loam  is  the  liberal 
use  of  limestone  wherever  cropping  is  practiced.  This  type  is  quite  acid  and 


191S\ 


McDonough  County 


31- 


very  deficient  in  nitrogen ; and  the  limestone,  by  correcting  the  acidity  of  the 
soil,  is  especially  beneficial  to  the  clover  grown  to  increase  the  supply  of  ni- 
trogen. Where  this  soil  has  been  long  cultivated  and  thus  exposed  to  surface 
washing,  it  is  particularly  deficient  in  nitrogen;  indeed  on  such  lands  the  low 
supply  of  nitrogen  is  the  factor  that  first  limits  the  growth  of  grain  crops. 
This  fact  is  very  strikingly  illustrated  by  the  results  from  two  pot-culture 
experiments  reported  in  Tables  13  and  14,  and  shown  photographically  in 
Plates  6 and  7. 

In  one  experiment,  a large  quantity  of  the  typical  worn  hill  soil  was  col- 
lected from  two  different  places.1  Each  lot  of  soil  was  thoroly  mixed  and  put 
in  ten  four-gallon  jars.  Ground  limestone  was  added  to  all  the  jars  except 
the  first  and  last  in  each  set,  those  two  being  retained  as  control  or  check 
pots.  The  elements  nitrogen,  phosphorus,  and  potassium  were  added  singly 
and  in  combination,  as  shown  in  Table  13. 

As  an  average,  the  nitrogen  applied  produced  a yield  about  eight  times  as 
large  as  that  secured  without  the  addition  of  nitrogen.  While  some  variations 


Plate  6. — Wheat  in  Pot-Culture  Experiment  with  Yellow  Silt  Loam  of  Worn 
Hill  Land  (See  Table  13) 

Table  13.— Crop  Yields  in  Pot-Culture  Experiment  with  Yellow  Silt  Loam  of 
Worn  Hill  Land 
(Grams  per  pot) 


Pot 

No. 

Soil  treatment  applied 

Wheat 

Oats 

1 

2 

None 

Limestone 

3 

4 

5 

4 

3 

Limestone,  nitrogen 

26 

45 

4 

Limestone,  phosphorus  

3 

6 

5 

Limestone,  potassium  

3 ' 

5 

6 

Limestone,  nitrogen,  phosphorus 

34 

38 

7 

Limestone,  nitrogen,  potassium  

33 

46 

8 

Limestone,  phosphorus,  potassium 

2 

5 

9 

I Limestone,  nitrogen,  phosphorus,  potassium 

34 

38 

10 

None  

3 

5 

Average  yield  with  nitrogen 

32 

42 

Average  yield  without  nitrogen 

3 

5 

Average  gain  for  nitrogen 

29 

~37 

1Soil  for  wheat  pots  from  loess-covered  unglaciated  area,  and  that  for  oat  pots  from 
upper  Illinois  glaciation. 


32 


Soil  Eepoet  No.  7 


[September, 


in  yield  are  to  be  expected,  because  of  differences  in  the  individuality  of  seed 
or  other  uncontrolled  causes,  yet  there  is  no  doubting  the  plain  lesson  taught 
by  these  actual  trials  with  growing  plants. 

The  question  arises  next,  Where  is  the  farmer  to  secure  this  much-needed 
nitrogen?  To  purchase  it  in  commercial  fertilizer  would  cost  too  much; 
indeed,  under  average  conditions  the  cost  of  the  nitrogen  in  such  fertilizers  is 
greater  than  the  value  of  the  increase  in  crop  yields. 

There  is  no  need  whatever  to  purchase  nitrogen,  for  the  air  contains  an 
inexhaustible  supply  of  it,  which,  under  suitable  conditions,  the  farmer  can 
draw  upon,  not  only  without  cost,  but  with  profit  in  the  getting.  Clover,  alfalfa, 
cowpeas,  and  soybeans  are  not  only  worth  raising  for  their  own  sake,  but 
they  have  the  power  to  secure  nitrogen  from  the  atmosphere  if  the  soil  contains 
limestone  and  the  proper  nitrogen-fixing  bacteria. 

In  order  to  secure  further  information  along  this  line,  another  experiment 
with  pot  cultures  was  conducted  for  several  years  with  the  same  type  of  worn 
hill  soil  as  that  used  in  the  former  experiment.  The  results  are  reported  in 
Table  14. 

To  three  pots  (Nos.  3,  6,  and  9)  nitrogen  was  applied  in  commercial  form, 
at  an  expense  amounting  to  more  than  the  total  value  of  the  crops  produced. 
In  three  other  pots  (Nos.  2,  11,  and  12)  a crop  of  cowpeas  was  grown  during 
the  late  summer  and  fall  and  turned  under  before  the  wheat  or  oats  were 
planted.  Pots  1 and  8 served  for  important  comparisons.  After  the  second 
catch  crop  of  cowpeas  had  been  turned  under,  the  yield  from  Pot  2 exceeded 
that  from  Pot  3 ; and  in  the  subsequent  years  the  legume  green  manures  pro- 
duced, as  an  average,  rather  better  results  than  the  commercial  nitrogen.  This 
experiment  confirms  that  reported  in  Table  13,  in  showing  the  very  great  need 
of  nitrogen  for  the  improvement  of  this  type  of  soil,  and  it  also  shows  that 
nitrogen  need  not  be  purchased  but  that  it  can  be  obtained  from  the  air  by 
growing  legume  crops  and  plowing  them  under  as  green  manure.  Of  course, 
the  soil  can  be  very  markedly  improved  by  feeding  the  legume  crops  to  live 
stock  and  returning  the  resulting  farm  manure  to  the  land,  if  sufficiently 
frequent  crops  of  legumes  are  grown  and  if  the  farm  manure  produced  is 
sufficiently  abundant  and  is  saved  and  applied  with  care. 

As  a rule,  it  is  not  advisable  to  try  to  enrich  this  type  of  soil  in  phos- 
phorus, for  with  the  erosion  that  is  sure  to  occur  to  some  extent,  the  phos- 
phorus supply  will  be  renewed  from  the  subsoil. 

One  of  the  most  profitable  crops  to  grow  on  this  land  is  alfalfa.  To  get 
alfalfa  well  started  requires  the  liberal  use  of  limestone,  thoro  inoculation  with 
nitrogen-fixing  bacteria,  and  a moderate  application  of  farm  manure.  If 
manure  is  not  available,  it  is  well  to  apply  about  500  pounds  per  acre  of  acid 
phosphate,  or  steamed  bone  meal,  mix  it  with  the  soil,  by  disking  if  possible, 
and  then  plow  it  under.  The  limestone  (about  5 tons)  should  be  applied  after 
plowing  and  should  be  mixed  with  the  surface  soil  in  the  preparation  of  the 
seed  bed.  The  special  purpose  of  this  treatment  is  to  give  the  alfalfa  a quick 
start  in  order  that  it  may  grow  rapidly  and  thus  protect  the  soil  from  washing. 

Light  Gray  Silt  Loam  on  Tight  Clay  (532) 

Light  gray  silt  loam  on  tight  clay  in  McDonough  county  aggregates  only 
2.53  square  miles  (1,619  acres),  or  .44  percent  of  the  county.  It  usually 
appears  in  small  areas  chiefly  in  the  southwestern  and  southern  part  of  the 
county.  In  topography  this  type  is  flat,  with  poor  drainage,  altho  not  swampy. 
It  was  formerly  covered  with  hickory,  white  oak,  and  “black  jack.” 


191S  J 


McDonough  County 


33 


The  surface  soil,  o to  inches,  is  a white  or  very  light  gray  silt  loam, 
incoherent,  friable,  and  porous.  Iron  concretions  are  usually  present.  The 
organic-matter  content  is  very  low,  amounting  to  only  1.4  percent,  or  14 
tons  per  acre. 

The  subsurface  is  a light  gray  silt  loam  extending  to  a depth  of  16  to  18 
inches.  It  becomes  more  clayey  with  depth  and  contains  only  a very  small 
amount  of  organic  matter. 

The  subsoil  is  a tight,  compact,  clayey  silt  or  silty  clay. 

Besides  being  very  deficient  in  organic  matter,  this  type  of  soil  contains 
no  limestone,  and  consequently  is  in  poor  physical  condition.  It  runs  together 
badly,  and  does  not  retain  moisture  well,  owing  to  the  strong  capillarity  in 
the  surface  and  subsurface  strata  caused  by  lack  of  organic  matter. 

In  the  management  of  this  type,  ground  limestone  should  be  used  liber- 
ally, rock  phosphate  should  be  added,  and  the  content  of  organic  matter 
should  be  increased  in  every  practical  way.  Deep-rooting  crops,  such  as 
red,  mammoth,  or  sweet  clover,  will  loosen  the  tight  clay  subsoil  as  well  as 
supply  the  top  soil  (surface  and  subsurface  strata)  with  organic  matter  and 
nitrogen.  Where  this  type  is  not  well  drained,  alsike  will  grow  better  than 
red  clover.  Crop  residues  should  be  plowed  under  or  plenty  of  farm  manure 
supplied.  Pasturing  is  one  of  the  best  uses  that  can  be  made  of  this  land, 
and  even  when  used  for  this  purpose  it  may  well  be  liberally  supplied  with 
limestone,  organic  matter,  and  phosphorus  before  being  seeded  down. 


Plate  7. — Wheat  in  Pot-Culture  Experiment  with  Yellow  Silt  Loam  of  Worn 


Hill  Land  (See  Table  14) 


Table  14 — Crop  Yields  in  Pot -Culture  Experiment  with  Yellow  Silt  Loam 
oe  Worn  Hill  Land  and  Nitrogen  Fixing  Green  Manure  Crops 
(Grams  per  pot) 


Pot 

No. 

Soil  treatment 

1903 

Wheat 

1904 

Wheat 

1905 

Wheat 

1906 

Wheat 

1907 

Oats 

1 

None.  

5 

4 

4 

4 

6 

2 

Limestone,  legume  

10 

17 

26 

19 

37 

11 

Limestone,  legume,  phosphorus 

14 

19 

20 

18 

27 

12 

Limestone,  legume,  phosphorus, 

potassium 

16 

20 

21 

19 

30 

3 

Limestone,  nitrogen 

Limestone,  nitrogen,  phosphorus 

17 

14 

15 

9 

28 

6 

26 

20 

18 

18 

30 

9 

Limestone,  nitrogen,  phosphorus, 

potassium 

31 

34 

21 

20 

26 

8 

Limestone,  phosphorus,  potassium 

3 

3 

5 

3 

7- 

34 


Soil  Keport  No.  7 


[September, 


(c)  Swamp  and  Bottom-Land  Soils 

The  bottom-land  soils  are  derived  from  material  washed  from  the  up- 
land, and  must  therefore  have  some  relation  to  the  upland  soils.  They  dif- 
fer in  that  they  are  more  variable  in  physical  composition  than  any  single 
upland  type,  and  the  brown  color  extends  into  them  to  a greater  depth. 

Deep  Brown  Silt  Loam  (1326) 

The  bottom  land  in  McDonough  county  is  made  up  entirely  of  deep 
brown  silt  loam.  It  occurs  in  long,  narrow  strips  varying  from  a few  rods 
to  nearly  a mile  in  width,  and  occupies  14.02  square  miles  (8,973  acres),  or 
2.44  percent  of  the  area  of  the  county.  In  topography  it  is  flat  or  with  very 
slight  undulations  that  represent  old  stream  or  overflow  channels. 

The  surface  soil,  o to  6^3  inches,  is  a brown  silt  loam  containing  4 per- 
cent of  organic  matter,  or  40  tons  per  acre.  It  is  probably  easier  to  main- 
tain the  fertility  and  the  organic  matter  in  this  deep  brown  silt  loam  than  in 
the  upland  soils,  because  of  its  occasional  overflow  and  the  consequent 
deposition  of  material  rich  in  humus  and  plant  food.  In  physical  composi- 
tion this  type  varies  from  a clay  loam  to  a sandy  loam,  but  the  areas  of  these 
extreme  types,  especially  of  the  sandy  loam,  are  so  small  and  so  changeable 
that  to  show  them  on  the  map  really  does  not  mean  very  much,  as  the  next 
flood  may  change  their  boundaries. 

The  subsurface  is  also  a brown  silt  loam,  becoming  lighter  in  color,  and 
frequently  in  texture,  with  depth.  It  contains  an  average  of  2.5  percent  of 
organic  matter. 

The  subsoil  is  a yellowish  drab  silt  loam,  varying  in  physical  composition 
either  to  a clayey  silt  or  to  a sandy  loam,  or  even  to  a sand  in  the  lower  sub- 
soil. 

Where  proper  drainage  is  secured,  this  type  is  quite  productive.  As  a 
rule,  where  it  is  subject  to  frequent  overflow  nothing  is  needed  except  good 
farming.  Even  the  systematic  rotation  of  crops  is  not  so  important  where 
the  land  is  subject  to  occasional  overflow,  but  where  it  lies  high  or  is  pro- 
tected from  overflow  by  dikes,  a rotation  including  legume  crops  should  be 
practiced,  and  ultimately  provision  should  be  made  for  the  enrichment  of 
such  protected  land  in  both  phosphorus  and  organic  matter,  and  if  acid,  in 
limestone. 


191S] 


McDonough  County 


35 


APPENDIX 

A study  of  the  soil  map  and  the  tabular  statements  concerning  crop  re- 
quirements, the  plant-food  content  of  the  different  soil  types,  and  the  actual 
results  secured  from  definite  field  trials  with  different  methods  or  systems 
of  soil  improvement,  and  a careful  study  of  the  discussion  of  general  prin- 
ciples and  of  the  descriptions  of  individual  soil  types,  will  furnish  the  most 
necessary  and  useful  information  for  the  practical  improvement  and  perma- 
nent preservation  of  the  productive  power  of  every  kind  of  soil  on  every 
farm  in  the  county. 

More  complete  information  concerning  the  most  extensive  and  impor- 
tant soil  types  in  the  great  soil  areas  in  all  parts  of  Illinois  is  contained  in 
Bulletin  123,  “The  Fertility  in  Illinois  Soils,”  which  contains  a colored  gen- 
eral survey  soil  map  of  the  entire  state. 

Other  publications  of  general  interest  are : 

Bulletin  No.  76,  “Alfalfa  on  Illinois  Soils” 

Bulletin  No.  94,  “Nitrogen  Bacteria  and  Legumes” 

Bulletin  No.  115,  “Soil  Improvement  for  the  Worn  Hill  Lands  of  Illinois” 

Bulletin  No.  125,  “Thirty  Years  of  Crop  Rotation  on  the  Common  Prairie  Lands  of 
Illinois” 

Circular  No.  no,  “Ground  Limestone  for  Acid  Soils” 

Circular  No.  127,  “Shall  We  Use  Natural  Rock  Phosphate  or  Manufactured  Acid  Phos- 
phate for  the  Permanent  Improvement  of  Illinois  Soils?” 

Circular  No.  129,  “The  Use  of  Commercial  Fertilizers” 

Circular  No.  149,  “Some  "Results  of  Scientific  Soil  Treatment”  and  “Methods  and  Re- 
sults of  Ten  Years’  Soil  Investigation  in  Illinois” 

Circular  No.  165,  “Shall  We  Use  ‘Complete’  Commercial  Fertilizers  in  the  Corn  Belt?” 

NOTE. — Information  as  to  where  to  obtain  limestone,  phosphate,  bone  meal,  and  po- 
tasium  salts,  methods  of  application,  etc.,  will  also  be  found  in  Circulars  no  and  165. 


Soil  Survey  Methods 

The  detail  soil  survey  of  a county  consists  essentially  of  indicating  on 
a map  the  location  and  extent  of  the  different  soil  types;  and,  since  the 
value  of  the  survey  depends  upon  its  accuracy,  every  reasonable  means  is 
employed  to  make  it  trustworthy.  To  accomplish  this  object  three  things 
are  essential:  first,  careful,  well-trained  men  to  do  the  work;  second,  an  ac- 
curate base  map  upon  which  to  show  the  results  of  their  work:  and,  third, 
the  means  necessary  to  enable  the  men  to  place  the  soil-type  boundaries, 
streams,  etc.,  accurately  upon  the  map. 

The  men  selected  for  the  work  must  be  able  to  keep  their  location 
exactly  and  to  recognize  the  different  soil  types,  with  their  principal  varia- 
tions and  limits,  and  they  must  show  these  upon  the  maps  correctly.  A 
definite  system  is  employed  in  checking  up  this  work.  As  an  illustration,  one 
soil  expert  will  survey  and  map  a strip  80  rods  or  160  rods  wide  and  any 
convenient  length,  while  his  associate  will  work  independently  on  another 
strip  adjoining  this  area,  and,  if  the  work  is  correctly  done,  the  soil  type 
boundaries  will  match  up  on  the  line  between  the  two  strips. 

An  accurate  base  map  for  field  use  is  absolutely  necessary  for  soil  map- 
ping. The  base  maps  are  made  on  a scale  of  one  inch  to  the  mile.  The 
official  data  of  the  original  or  subsequent  land  survey  are  used  as  a basis  in 
the  construction  of  these  maps,  while  the  most  trustworthy  county  map  avail- 
able is  used  in  locating  temporarily  the  streams,  roads,  and  railroads.  Since 
the  best  of  these  published  maps  have  some  inaccuracies,  the  location  of  every 
road,  stream,  and  railroad  must  be  verified  by  the  soil  surveyors,  and  cor- 


36 


Soil  Repoet  No.  7 


[September, 


rected  if  wrongly  located.  In  order  to  make  these  verifications  and  correc- 
tions, each  survey  party  is  provided  with  an  odometer  for  measuring  dis- 
tances, and  a plane  table  for  determining  directions  of  roads,  railroads,  etc. 

Each  surveyor  is  provided  with  a base  map  of  the  proper  scale,  which  is 
carried  with  him  in  the  field ; and  the  soil-type  boundaries,  additional  streams, 
and  necessary  corrections  are  placed  in  their  proper  locations  upon  the  map 
while  the  mapper  is  on  the  area.  Each  section,  or  square  mile,  is  divided  into 
40-acre  plots  on  the  map,  and  the  surveyor  must  inspect  every  ten  acres  and 
determine  the  type  or  types  of  soil  composing  it.  The  different  types  are 
indicated  on  the  map  by  different  colors,  pencils  for  this  purpose  being  car- 
ried in  the  field. 

A small  auger  40  inches  long  forms  for  each  man  an  invaluable  tool  with 
which  he  can  quickly  secure  samples  of  the  different  strata  for  inspection. 
An  extension  for  making  the  auger  80  inches  long  is  taken  by  each  party, 
so  that  any  peculiarity  of  the  deeper  subsoil  layers  may  be  studied.  Each 
man  carries  a compass  to  aid  in  keeping  directions.  Distances  along  roads 
are  measured  by  an  odometer  attached  to  the  axle  of  the  vehicle,  while  dis- 
tances in  the  field  off  the  roads  are  determined  by  pacing,  an  art  ;n  which 
the  men  become  expert  by  practice.  The  soil  boundaries  can  thus  be  located 
with  as  high  a degree  of  accuracy  as  can  be  indicated  by  pencil  on  the 
scale  of  one  inch  to  the  mile. 


Soil  Characteristics 

The  unit  in  the  soil  survey  is  the  soil  type,  and  each  type  possesses  more 
or  less  definite  characteristics.  The  line  of  separation  between  adjoining 
types  is  usually  distinct,  but  sometimes  one  type  grades  into  another  so 
gradually  that  it  is  very  difficult  to  draw  the  line  between  them.  In  such 
exceptional  cases,  some  slight  variation  in  the  location  of  soil-type  boundaries 
is  unavoidable. 

Several  factors  must  be  taken  into  account  in  establishing  soil  types. 
These  are  (1)  the  geological  origin  of  the  soil,  whether  residual,  glacial, 
loessial,  alluvial,  colluvial,  or  cumulose;  (2)  the  topography,  or  lay  of  the 
land ; (3)  the  native  vegetation,  as  forest  or  prairie  grasses;  (4)  the  structure, 
or  the  depth  and  character  of  the  surface,  subsurface,  and  subsoil;  (5)  the 
physical,  or  mechanical, composition  of  the  different  strata  composing  the  soil, 
as  the  percentages  of  gravel,  sand,  silt,  clay,  and  organic  matter  which  they 
contain;  (6)  the  texture,  or  porosity,  granulation,  friability,  plasticity,  etc.; 
(7)  the  color  of  the  strata;  (8)  the  natural  drainage;  (9)  agricultural 
value,  based  upon  its  natural  productiveness;  (10)  the  ultimate  chemical 
composition  and  reaction. 

The  common  soil  constituents  are  indicated  in  the  following  outline : 


Constituents  of  Soils 


Organic  f Comprising  undecomposed  and  partially  decayed 

Matter  1 vegetable  material 


Soil 

Constituents 


Inorganic 

Matter 


Clay 

mm.1  and 

less 

Silt 

mm.  to  .03 

mm. 

Sand 

03 

mm.  to  1. 

mm. 

Gravel 

mm.  to  32 

mm. 

Stones 

32. 

, mm.  and 

over 

1 25  millimeters  equal  1 inch.  > 

Further  discussion  of  these  constituents  is  given  in  Circular  82. 


1913  \ 


McDonough  County 


37 


Groups  op  Son,  Types 

The  following  gives  the  different  general  groups  of  soils: 

Peats — Consisting  of  35  percent  or  more  of  organic  matter,  sometimes 
mixed  with  more  or  less  sand  or  silt. 

Peaty  loams — 15  to  35  percent  of  organic  matter  mixed  with  much  sand 
and  silt  and  a little  clay. 

Mucks — 15  to  35  percent  of  partly  decomposed  organic  matter  mixed 
with  much  clay  and  some  silt. 

Clays — Soils  with  more  than  25  percent  of  clay,  usually  mixed  with  much 

silt. 

Clay  loams — Soils  with  from  15  to  25  percent  of  clay,  usually  mixed 
with  much  silt  and  some  sand. 

Silt  loams — Soils  with  more  than  50  percent  of  silt  and  less  than  15 
percent  of  clay,  mixed  with  some  sand. 

Loams — Soils  with  from  30  to  50  percent  of  sand  mixed  with  much  silt 
and  a little  clay. 

Sandy  loams— Soils  with  from  50  to  75  percent  of  sand. 

Fine  sandy  loams — Soils  with  from  50  to  75  percent  of  fine  sand  mixed 
with  much  silt  and  little  clay. 

Sands — Soils  with  more  than  75  percent  of  sand. 

Gravelly  loams — Soils  with  15  to  50  percent  of  gravel  with  much  sand 
and  some  silt. 

Gravels — Soils  with  more  than  50  percent  of  gravel. 

Stony  loams — Soils  containing  a considerable  number  of  stones  over  one 
inch  in  diameter. 

Rock  outcrop — Usually  ledges  of  rock  having  no  agricultural  value. 

More  or  less  organic  matter  is  found  in  nearly  all  the  above  classes. 

Supply  and  Liberation  op  Plant  Food 

The  productive  capacity  of  land  in  humid  sections  depends  almost  wholly 
upon  the  power  of  the  soil  to  feed  the  crop ; and  this,  in  turn,  depends  both 
upon  the  stock  of  plant  food  contained  in  the  soil  and  upon  the  rate  at  which 
this  is  liberated,  or  rendered  soluble  and  available  for  use  in  plant  growth. 
Protection  from  weeds,  insects,  and  fungous  diseases,  tho  exceedingly  im- 
portant, is  not  a positive  but  a negative  factor  in  crop  production. 

The  chemical  analysis  of  the  soil  gives  the  invoice  of  fertility  actually 
present  in  the.  soil  strata  sampled  and  analyzed,  but  the  rate  of  liberation  is 
governed  by  many  factors,  some  of  which  may  be  controlled  by  the  farmer, 
while  others  are  largely  beyond  his  control.  Chief  among  the  important 
controllable  factors  which  influence  the  liberation  of  plant  food  are  lime- 
stone and  decaying  organic  matter,  which  may  be  added  to  the  soil  by  direct 
application  of  ground  limestone  and  farm  manure.  Organic  matter  may  be 
supplied  also  by  green-manure  crops  and  crop  residues,  such  as  clover,  cow- 
peas,  straw,  and  cornstalks.  The  rate  of  decay  of  organic  matter  depends 
largely  upon  its  age  and  origin,  and  it  may  be  hastened  by  tillage.  The 
chemical  analysis  shows  correctly  the  total  organic  carbon,  which  represents, 
as  a rule,  but  little  more  than  half  the  organic  matter;  so  that  20,000 
pounds  of  organic  carbon  in  the  plowed  soil  of  an  acre  correspond  to  nearly 


38 


Soil  Eepoet  No.  7 


[, September , 


20  tons  of  organic  matter.  But  this  organic  matter  consists  largely  of  the 
old  organic  residues  that  have  accumulated  during  the  past  centuries  because 
they  were  resistant  to  decay,  and  2 tons  of  clover  or  cowpeas  plowed  under 
may  have  greater  power  to  liberate  plant  food  than  the  20tons  of  old,  inactive 
organic  matter.  The  recent  history  of  the  individual  farm  or  field  must  be 
depended  upon  for  information  concerning  recent  additions  of  active  organic 
matter,  whether  in  applications  of  farm  manure,  in  legume  crops,  or  in  grass- 
root  sods  of  old  pastures. 

Probably  no  agricultural  fact  is  more  generally  known  by  farmers  and 
landowners  than  that  soils  differ  in  productive  power.  Even  tho  plowed 
alike  and  at  the  same  time,  prepared  the  same  way,  planted  the  same  day 
with  the  same  kind  of  seed,  and  cultivated  alike,  watered  by  the  same  rains 
and  warmed  by  the  same  sun,  nevertheless  the  best  acre  may  produce  twice 
as  large  a crop  as  the  poorest  acre  on  the  same  farm,  if  not,  indeed,  in  the 
same  field;  and  the  fact  should  be  repeated  and  emphasized  that  with  the 
normal  rainfall  of  Illinois  the  productive  power  of  the  land  depends  primarily 
upon  the  stock  of  plant  food  contained  in  the  soil  and  upon  the  rate  at  which 
it  is  liberated,  just  as  the  success  of  the  merchant  depends  primarily  upon 
his  stock  of  goods  and  the  rapidity  of  sales.  In  both  cases  the  stock  of  any 
commodity  must  be  increased  or  renewed  whenever  the  supply  of  such  com- 
modity becomes  so  depleted  as  to  limit  the  success  of  the  business,  whether 
on  the  farm  or  in  the  store. 

As  the  organic  matter  decays,  certain  decomposition  products  are  formed, 
including  much  carbonic  acid,  some  nitric  acid,  and  various  organic  acids, 
and  these  have  power  to  act  upon  the  soil  and  dissolve  the  essential  mineral 
plant  foods,  thus  furnishing  soluble  phosphates,  nitrates,  and  other  salts  of 
potassium,  magnesium,  calcium,  etc.,  for  the  use  of  the  growing  crop.  , 

As  already  explained,  fresh  organic  matter  decomposes  much  more  rap- 
idly than  the  old  humus,  which  represents  the  organic  residues  most  resistant 
to  decay  and  which  consequently  has  accumulated  in  the  soil  during  the 
past  centuries.  The  decay  of  this  old  humus  can  be  hastened  both  by  tillage, 
which  maintains  a porous  condition  and  thus  permits  the  oxygen  of  the  air 
to  enter  the  soil  more  freely  and  to  effect  the  more  rapid  oxidation  of  the 
organic  matter,  and  also  by  incorporating  with  the  old,  resistant  residues 
some  fresh  organic  matter,  such  as  farm  manure,  clover  roots,  etc.,  which 
decay  rapidly  and  thus  furnish  or  liberate  organic  matter  and  inorganic  food 
for  bacteria,  the  bacteria,  under  such  favorable  conditions,  appearing  to  have 
power  to  attack  and  decompose  the  old  humus.  It  is  probably  for  this  reason 
that  peat,  a very  inactive  and  inefficient  fertilizer  when  used  by  itself,  becomes 
much  more  effective  when  incorporated  with  fresh  farm  manure;  so  that, 
when  used  together,  two  tons  of  the  mixture  may  be  worth  as  much  as  two 
tons  of  manure,  but  if  applied  separately,  the  peat  has  little  value.  Bacterial 
action  is  also  promoted  by  the  presence  of  limestone. 

The  condition  of  the  organic  matter  of  the  soil  is  indicated  more  or  less 
definitely  by  the  ratio  of  carbon  to  nitrogen.  As  an  average,  the  fresh 
organic  matter  incorporated  with  soils  contains  about  twenty  times  as  much 
carbon  as  nitrogen,  but  the  carbohydrates  ferment  and  decompose  much  more 
rapidly  than  the  nitrogenous  matter;  and  the  old  resistant  organic  residues, 
such  as  are  found  in  normal  subsoils,  commonly  contain  only  five  or  six  times 
as  much  carbon  as  nitrogen.  Soils  of  normal  physical  composition,  such 
as  loam,  clay  loam,  silt  loam,  and  fine  sandy  loam,  when  in  good  productive 


1918] 


McDonough  County 


39 


condition,  contain  about  twelve  to  fourteen  times  as  much  carbon  as  nitrogen 
in  the  surface  soil ; while  in  old,  worn  soils  that  are  greatly  in  need  of  fresh, 
active,  organic  manures,  the  ratio  is  narrower,  sometimes  falling  below  ten  of 
carbon  to  one  of  nitrogen.  (Except  in  newly  made  alluvial  soils,  the  ratio 
is  usually  narrower  in  the  subsurface  and  subsoil  than  in  the  surface  stratum.) 

It  should  be  kept  in  mind  that  crops  are  not  made  out  of  nothing.  They 
are  composed  of  ten  different  elements  of  plant  food,  every  one  of  which  is 
absolutely  essential  for  the  growth  and  formation  of  every  agricultural  plant. 
Of  these  ten  elements  of  plant  food,  only  two  (carbon  and  oxygen)  are 
secured  from  the  air  by  all  agricultural  plants,  only  one  (hydrogen)  from 
water,  and  seven  from  the  soil.  Nitrogen,  one  of  these  seven  elements 
secured  from  the  soil  by  all  plants,  may  also  be  secured  from  the  air  by  one 
class  of  plants  (legumes),  in  case  the  amount  liberated  from  the  soil  is  insuf- 
ficient; but  even  these  plants  (which  include  only  the  clovers,  peas,  beans,  and 
vetches,  among  our  common  agricultural  plants)  secure  from  the  soil  alone 
six  elements  (phosphorus,  potassium,  magnesium,  calcium,  iron  and  sulfur), 
and  also  utilize  the  soil  nitrogen  so  far  as  it  becomes  soluble  and  available 
during  their  period  of  growth. 

Plants  are  made  of  plant-food  elements  in  just  the  same  sense  that 
a building  is  made  of  wood  and  iron,  brick,  stone,  and  mortar.  Without 
materials,  nothing  material  can  be  made.  The  normal  temperature,  sunshine, 
rainfall,  and  length  of  season  in  central  Illinois  are  sufficient  to  produce 
50  bushels  of  wheat  per  acre,  100  bushels  of  corn,  100  bushels  of  oats,  and 
4 tons  of  clover  hay;  and,  where  the  land  is  properly  drained  and  properly 
tilled,  such  crops  would  frequently  be  secured  if  the  plant  foods  were  present 
in  sufficient  amounts  and  liberated  at  a sufficiently  rapid  rate  to  meet  the  abso- 
lute needs  of  the  crops. 

Crop  Requirements 

The  accompanying  table  shows  the  requirements  of  such  crops  for  the 
five  most  important  plant-food  elements  which  the  soil  must  furnish.  (Iron 
and  sulfur  are  supplied  normally  in  sufficient  abundance  compared  with  the 
amounts  needed  by  plants,  so  that  they  are  not  known  ever  to  limit  the  yield 
of  general  farm  crops  grown  under  normal  conditions.) 


Tabus  A. — Plant  Food  in  Wheat,  Corn,  Oats,  and  Clover 


Produce 

Nitro- 

gen, 

pounds 

Phos-  I 
phorus, 
pounds 

Potas- 

sium, 

pounds 

Magne- 

sium, 

pounds 

Cal- 

cium, 

pounds 

Kind 

Amount 

Wheat,  grain 

50  bu. 

71 

12 

13 

4 

1 

Wheat  straw 

2 yz  tons 

25 

4 

45 

4 

10 

Corn,  grain  

100  bu. 

100 

17 

19 

7 

1 

Corn  stover 

3 tons 

48 

6 

52 

10 

21 

Corn  cobs  

% ton 

2 

2 

Oats,  grain 

100  bu. 

66 

11 

16 

4 

2 

Oat  straw 

2l/z  tons 

31 

5 

52 

7 

IS 

Clover  seed  

4 bu. 

7 

2 

3 

1 

1 

Clovei  hay  . 

4 tons 

160 

20 

120 

31 

117 

Total  in  grain  and  seed 

244 1 

42 

51 

16 

4 

Total  in  four  crops 

5101 

77 

322 

68 

168 

‘These  amounts  include  the  nitrogen  contained  in  the  clover  seed  or  hay,  which, 
however,  may  be  secured  from  the  air. 


Soil  Eepoet  No.  7 


[September, 


40 


To  be  sure,  these  are  large  yields,  but  shall  we  try  to  make  possible  the 
production  of  yields  only  half  or  a quarter  as  large  as  these,  or  shall  we 
set  as  our  ideal  this  higher  mark,  and  then  approach  it  as  nearly  as  possible 
with  profit?  Among  the  four  crops,  corn  is  the  largest,  with  a total  yield 
of  more  than  six  tons  per  acre;  and  yet  the  ioo-bushel  crop  of  corn  is  often 
produced  on  rich  pieces  of  land  in  good  seasons.  In  very  practical  and 
profitable  systems  of  farming,  the  Illinois  Experiment  Station  has  produced, 
as  an  average  of  the  six  years  1905  to  1910,  a yield  of  87  bushels  of  corn 
per  acre  in  grain  farming  (with  limestone  and  phosphorus  applied,  and  with 
crop  residues  and  legume  crops  turned  under),  and  90  bushels  per  acre  in 
live-stock  farming  (with  limestone,  phosphorus,  and  manure). 

The  importance  of  maintaining  a rich  surface  soil  cannot  be  too  strongly 
emphasized.  This  is  well  illustrated  by  data  from  the  Rothamsted  Experi- 
ment Station,  the  oldest  in  the  world.  Thus  on  Broadbalk  field,  where  wheat 
has  been  grown  since  1844,  the  average  yields  for  the  ten  years  1892  to  1901 
were  12.3  bushels  per  acre  on  Plot  3 (unfertilized)  and  31.8  bushels  on 
Plot  7 (well  fertilized),  but  the  amounts  of  both  nitrogen  and  phosphorus 
in  the. subsoil  (9  to  27  inches)  were  distinctly  greater  in  Plot  3 than  in 
Plot  7,  thus  showing  that  the  higher  yields  from  Plot  7 were  due  to  the 
fact  that  the  plowed  soil  had  been  enriched.  In  1893  Plot  7 contained  per 
acre  in  the  surface  soil  (o  to  9 inches)  about  600  pounds  more  nitrogen  and 
900  pounds  more  phosphorus  than  Plot  3.  Even  a rich  subsoil  has  little 
value  if  it  lies  beneath  a worn-out  surface. 

Methods  of  Liberating  Plant  Food 

Limestone  and  decaying  organic  matter  are  the  principal  materials  the 
farmer  can  utilize  most  profitably  to  bring  about  the  liberation  of  plant  food. 

The  limestone  corrects  the  acidity  of  the  soil  and  thus  encourages  the 
development  not  only  of  the  nitrogen-gathering  bacteria  which  live  in  the 
nodules  .on  the  roots  of  clover,  cowpeas,  and  other  legumes,  but  also  the 
nitrifying  bacteria,  which  have  power  to  transform  the  insoluble  and  unavail- 
able organic  nitrogen  into  soluble  and  available  nitrate  nitrogen. 

At  the  same  time,  the  products  of  this  decomposition  have  power  to  dis- 
solve the  minerals  contained  in  the  soil,  such  as  potassium  and  magnesium, 
and  also  to  dissolve  the  insoluble  phosphate  and  limestone  which  may  be 
applied  in  low-priced  forms. 

Tillage,  or  cultivation,  also  hastens  the  liberation  of  plant  food  by  permit- 
ting the  air  to  enter  the  soil  and  burn  out  the  organic  matter;  but  it  should 
never  be  forgotten  that  tillage  is  wholly  destructive,  that  it  adds  nothing 
whatever  to  the  soil,  but  always  leaves  the  soil  poorer.  Tillage  should  be 
practiced  so  far  as  is  necessary  to  prepare  a suitable  seed-bed  for  root  devel- 
opment and  also  for  the  purpose  of  killing  weeds,  but  more  than  this  is 
unnecessary  and  unprofitable  in  seasons  of  normal  rainfall ; and  it  is  much 
better  actually  to  enrich  the  soil  by  proper  applications  or  additions,  including 
limestone  and  organic  matter  (both  of  which  have  power  to  improve  the 
physical  condition  as  well  as  to  liberate  plant  food)  than  merely  to  hasten 
soil  depletion  by  means  of  excessive  cultivation. 

Permanent  Soil  Improvement 

The  best  and  most  profitable  methods  for  the  permanent  improvement  of 
the  common  soils  of  Illinois  are  as  follows : 


1918] 


McDonough  County 


41 


(i)  If  the  soil  is  acid,  apply  at  least  two  tons  per  acre  of  ground  lime- 
stone, preferably  at  times  magnesian  limestone  (CaC03MgC03),  which 
contains  both  calcium  and  magnesium  and  has  slightly  greater  power  to  cor- 
rect soil  acidity,  ton  for  ton,  than  the  ordinary  calcium  limestone  (CaC03)  ; 
and  continue  to  apply  about  two  tons  per  acre  of  ground  limestone  every  four 
or  five  years,  On  strongly  acid  soils,  or  in  preparing  the  land  for  alfalfa,  five 
tons  per  acre  of  ground  limestone  may  well  be  used  for  the  first  application. 

(2)  Adopt  a good  rotation  of  crops,  including  a liberal  use  of  legumes, 
and  increase  the  organic  matter  of  the  soil  either  by  plowing  under  the 
legume  crops  and  other  crop  residues  (straw  and  corn  stalks),  or  by  using 
for  feed  and  bedding  practically  all  the  crops  raised  and  returning  the 
manure  to  the  land  with  the  least  possible  loss.  No  one  can  say  in  advance 
what  will  prove  to  be  the  best  rotation  of  crops,  because  of  variation  in 
farms  and  farmers,  and  in  prices  for  produce,  but  the  following  are  suggested 
to  serve  as  models  or  outlines : 

First  year,  corn. 

Second  year,  corn. 

Third  year,  wheat  or  oats  (with  clover  or  clover  and  grass). 

Fourth  year,  clover  or  clover  and  grass. 

Fifth  year,  wheat  and  clover  or  grass  and  clover. 

Sixth  year,  clover  or  clover  and  grass. 

Of  course  there  should  be  as  many  fields  as  there  are  years  in  the  rota- 
tion. In  grain  farming,  with  small  grain  grown  the  third  and  fifth  years,  most 
of  the  coarse  products  should  be  returned  to  the  soil,  and  the  clover  may  be 
clipped  and  left  on  the  land  (only  the  clover  seed  being  sold  the  fourth  and 
sixth  years)  ; or,  in  live-stock  farming,  the  field  may  be  used  three  years  for 
timothy  and  clover  pasture  and  meadow  if  desired.  The  system  may  be 
reduced  to  a five-year  rotation  by  cutting  out  either  the  second  or  the  sixth 
year,  and  to  a four-year  system  by  omitting  the  fifth  and  sixth  years. 

With  two  years  of  corn,  followed  by  oats  with  clover-seeding  the  third 
year,  and  by  clover  the  fourth  year,  all  produce  can  be  used  for  feed  and 
bedding  if  other  land  is  available  for  permanent  pasture.  Alfalfa  may  be 
grown  on  a fifth  field  for  four  or  eight  years,  which  is  to  be  alternated  with 
one  of  the  four;  or  the  alfalfa  may  be  moved  every  five  years,  and  thus 
rotated  over  all  five  fields  every  twenty-five  years. 

Other  four-year  rotations  more  suitable  for  grain  farming  are : 

Wheat  (and  clover),  corn,  oats,  and  clover;  or  corn  (and  clover),  cowpeas,  wheat, 
and  clover.  (Alfalfa  may  be  grown  on  a fifth  field  and  rotated  every  five  years, 
the  hay  being  sold.) 

Good  three-year  rotations  are: 

Corn,  oats,  and  clover;  corn,  wheat,  and  clover;  or  wheat  (and  clover),  corn  (and 
clover),  and  cowpeas,  in  which  two  cover  crops  and  one  regular  crop  of  legumes 
are  grown  in  three  years. 

A five-year  rotation  of  (1)  corn  (and  clover),  (2)  cowpeas,  (3)  wheat,’ 
(4)  clover,  and  (5)  wheat  (and  clover)  allows  legumes  to  be  seeded  four 
times,  and  alfalfa  may  be  grown  on  a sixth  field  for  five  or  six  years  in  the 
combination  rotation,  alternating  between  two  fields  every  five  years,  or 
rotating  over  all  the  fields  if  moved  every  six  years. 

To  avoid  clover  sickness  it  may  sometimes  be  necessary  to  substitute  sweet 
clover  or  alsike  for  red  clover  in  about  every  third  rotation,  and  at  the  same 


42 


Soil  Report  No.  7 


[ September , 


time  to  discontinue  its  use  in  the  cover-crop  mixture.  If  the  corn  crop 
is  not  too  rank,  cowpeas  or  soybeans  may  also  be  used  as  a cover  crop  (seeded 
at  the  last  cultivation)  in  the  southern  part  of  the  state,  and,  if  necessary 
to  avoid  disease,  these  may  well  alternate  in  successive  rotations. 

For  easy  figuring  it  may  well  be  kept  in  mind  that  the  following  amounts 
of  nitrogen  are  required  for  the  produce  named : 

I bushel  of  oats  (grain  and  straw)  requires  i pound  of  nitrogen. 

i bushel  of  corn  (grain  and  stalks)  requires  1(4  pounds  of  nitrogen. 

i bushel  of  wheat  (grain  and  straw)  requires  2 pounds  of  nitrogen. 

1 ton  of  timothy  requires  24  pounds  of  nitrogen. 

1 ton  of  clover  contains  40  pounds  of  nitrogen. 

1 ton  of  cowpeas  contains  43  pounds  of  nitrogen. 

I ton  of  average  manure  contains  10  pounds  of  nitrogen. 

The  roots  of  clover  contain  about  half  as  much  nitrogen  as  the  tops,  and 
the  roots  of  cowpeas  contain  about  one-tenth  as  much  as  the  tops. 

Soils  of  moderate  productive  power  will  furnish  as  much  nitrogen  to 
clover  (and  two  or  three  times  as  much  to  cowpeas)  as  will  be  left  in  the 
roots  and  stubble.  For  grain  crops,  such  as  wheat,  corn,  and  oats,  about  two- 
thirds  of  the  nitrogen  is  contained  in  the  grain  and  one-third  in  the  straw 
or  stalks.  (See  also  discussion  of  “The  Potassium  Problem,”  on  pages  below.) 

(3)  On  all  lands  deficient  in  phosphorus  (except  on  those  susceptible 
to  serious  erosion  by  surface  washing  or  gullying)  apply  that  element  in 
considerably*  larger  amounts  than  are  required  to  meet  the  actual  needs  of 
the  crops  desired  to  be  produced.  The  abundant  information  thus  far  se- 
cured shows  positively  that  fine-ground  natural  rock  phosphate  can  be  used 
successfully  and  very  profitably,  and  clearly  indicates  that  this  material  will 
be  the  most  economical  form  of  phosphorus  to  use  in  all  ordinary  systems 
of  permanent,  profitable  soil  improvement.  The  first  application  may  well 
be  one  ton  per  acre,  and  subsequently  about  one-half  ton  per  acre  every  four 
or  five  years  should  be  applied,  at  least  until  the  phosphorus  content  of  the 
plowed  soil  reaches  2,000  pounds  per  acre,  which  may  require  a total  ap- 
plication of  from  three  to  five  or  six  tons  per  acre  of  raw  phosphate  con- 
taining \2l/2  percent  of  the  element  phosphorus. 

Steamed  bone  meal  and  even  acid  phosphate  may  be  used  in  emergencies, 
but  it  should  always  be  kept  in  mind  that  phosphorus  delivered  in  Illinois 
costs  about  3 cents  a pound  in  raw  phosphate  (direct  from  the  mine  in  car- 
load lots),  but  10  cents  a pound  in  steamed  bone  meal,  and  about  12  cents 
a pound  in  acid  phosphate,  both  of  which  cost  too  much  per  ton  to  permit 
their  common  purchase  by  farmers  in  carload  lots,  which  is  not  the  case 
with  limestone  or  raw  phosphate. 

Phosphorus  once  applied  to  the  soil  remains  in  it  until  removed  in  crops, 
unless  carried  away  mechanically  by  soil  erosion.  (The  loss  by  leaching 
is  only  about  1 y2  pounds  per  acre  per  annum,  so  that  more  than  150  years 
would  be  required  to  leach  away  the  phosphorus  applied  in  one  ton  of  raw 
phosphate.) 

The  phosphate  and  limestone  may  be  applied  at  any  time  during  the 
rotation,  but  a good  method  is  to  apply  the  limestone  after  plowing  and 
work  it  into  the  surface  soil  in  preparing  the  seed  bed  for  wheat,  oats,  rye, 
or  barley,  where  clover  is  to  be  seeded ; while  phosphate  is  best  plowed  under 
with  farm  manure,  clover,  or  other  green  manures,  which  serve  to  liberate 
the  phosphorus. 


1913 ] 


McDonough  County 


43 


(4)  Until  the  supply  of  decaying  organic  matter  has  been  made  ade- 
quate, on  the  poorer  types  of  upland  timber  and  gray  prairie  soils  some 
temporary  benefit  may  be  derived  from  the  use;  of  a soluble  salt  or  mixture 
of  salts,  such  as  kainit,  which  contains  both  potassium  and  magnesium  in 
soluble  form  and  also  some  common  salt  (sodium  chlorid).  About  600 
pounds  per  acre  of  kainit  applied  and  turned  under  with  the  raw  phosphate 
will  help  to  dissolve  the  phosphorus  as  well  as  to  furnish  available  potas- 
sium and  magnesium,  and  for  a few  years  such  use  of  kainit  will  no  doubt 
be  profitable  on  lands  deficient  in  organic  matter,  but  the  evidence  thus  far 
secured  indicates  that  its  use  is  not  absolutely  necessary  and  that  it  will  not 
be  profitable  after  adequate  provision  is  made  for  decaying  organic  matter, 
since  this  will  necessitate  returning  to  the  soil  either  all  produce  except  the 
grain  (in  grain  farming)  or  the  manure  produced  in  live-stock  farming. 
(Where  hay  or  straw  is  sold,  manure  should  be  bought.) 

On  soils  which  are  subject  to  surface  washing,  including  especially  the 
yellow  silt  loam  of  the  upland  timber  area,  and  to  some  extent  the  yellow- 
gray  silt  loam,  and  other  more  rolling  areas,  the  supply  of  minerals  in  the 
subsurface  and  subsoil  (which  gradually  renew  the  surface  soil)  tends  to 
provide  for  a low-grade  system  of  permanent  agriculture  if  some  use  is  made 
of  legume  plants,  as  in  long  rotations  with  much  pasture,  because  both  the 
minerals  and  nitrogen  are  thus  provided  in  some  amount  almost  permanently ; 
but  where  such  lands  are  farmed  under  such  a system,  not  more  than  two  or 
three  grain  crops  should  be  grown  during  a period  of  ten  or  twelve  years, 
the  land  being  kept  in  pasture  most  of  the  time ; and  where  the  soil  is  acid  a 
liberal  use  of  limestone,  as  top-dressings  if  necessary,  and  occasional  re- 
seeding with  clovers  will  benefit  both  the  pasture  and  indirectly  the  grain 
crops. 

Advantage  of  Crop  Rotation  and  Permanent  Systems 

It  should  be  noted  that  clover  is  not  likely  to  be  well  infected  with  the 
clover  bacteria  during  the  first  rotation  on  a given  farm  or  field  where  it 
has  not  been  grown  before  within  recent  years;  but  even  a partial  stand  of 
clover  the  first  time  will  probably  provide  a thousand  times  as  many  bac- 
teria for  the  next  clover  crop  as  one  could  afford  to  apply  in  artificial  inocu- 
lation, for  a single  root-tubercle  may  contain  a million  bacteria  developed 
from  one  during  the  season’s  growth. 

This  is  only  one  of  several  advantages  of  the  second  course  of  the  rota- 
tion over  the  first  course.  Thus  the  mere  practice  of  crop  rotation  is  an  ad- 
vantage, especially  in  helping  to  rid  the  land  of  insects  and  foul  grass  and 
weeds.  The  deep-rooting  clover  crop  is  an  advantage  to  subsequent  crops 
because  of  that  characteristic.  The  larger  applications  of  organic  manures 
(made  possible  by  the  larger  crops)  are  a great  advantage;  and  in  systems 
of  permanent  soil  improvement,  such  as  are  here  advised  and  illustrated, 
more  limestone  and  more  phosphorus  are  provided  than  are  needed  for  the 
meager  or  moderate  crops  produced  during  the  first  rotation,  and  conse- 
quently the  crops  in  the  second  rotation  have  the  advantage  of  such  accumu- 
lated residues  (well  incorporated  with  the  plowed  soil)  in  addition  to  the 
regular  applications  made  during  the  second  rotation. 

This  means  that  these  systems  tend  positively  toward  the  making  of 
richer  lands.  The  ultimate  analyses  recorded  in  the  tables  give  the  absolute 
invoice  of  these  Illinois  soils.  They  show  that  most  of  them  are  positively 
deficient  only  in  limestone,  phosphorus,  and  nitrogenous  organic  matter:  and 


44 


Soil  Report  No.  7 


[September, 


the  accumulated  information  from  careful  and  long-continued  investigations 
in  different  parts  of  the  United  States  clearly  establishes  the  fact  that  in  gen- 
eral farming  these  essentials  can  be  supplied  with  greatest  economy  and 
profit  by  the  use  of  ground  natural  limestone,  very  finely  ground  natural 
rock  phosphate,  and  legume  crops  to  be  plowed  under  directly  or  in  farm 
manure.  On  normal  soils  no  other  applications  are  absolutely  necessary, 
but,  as  already  explained,  the  addition  of  some  soluble  salt  in  the  beginning 
of  a system  of  improvement  on  some  of  these  soils  produces  temporary 
benefit,  and  if  some  inexpensive  salt,  such  as  kainit,  is  used,  it  may  produce 
sufficient  increase  to  more  than  pay  the  added  cost. 

The  Potassium  Problem 

As  reported  in  Illinois  Bulletin  123,  where  wheat  has  been  grown  every 
year  for  more  than  half  a century  at  Rothamsted,  England,  exactly  the  same 
increase  was  produced  (5.6  bushels  per  acre),  as  an  average  of  the  first 
24  years,  whether  potassium,  magnesium,  or  sodium  was  applied,  the  rate  of 
application  per  annum  being  200  pounds  of  potassium  sulfate  and  molecular 
equivalents  of  magnesium  sulfate  and  sodium  sulfate.  As  an  average  of 
60  years  (1852  to  1911),  the  yield  of  wheat  has  been  12.7  bushels  on  un- 
treated land,  23.3  bushels  where  86  pounds  of  nitrogen  and  29  pounds  of 
phosphorus  per  acre  per  annum  were  applied;  and,  as  further  additions,  85 
pounds  of  potassium  raised  the  yield  to  31.3  bushels;  52  pounds  of  mag- 
nesium raised  it  to  29.2  bushels;  and  50  pounds  of  sodium  raised  it  to 
29.5  bushels.  Where  potassium  was  applied,  the  average  wheat  crop  re- 
moved 40  pounds  of  that  element  in  the  grain  and  straw,  or  three  times  as 
much  as  would  be  removed  in  the  grain  only  for  such  crops  as  are  suggested 
in  Table  A.  The  Rothamsted  soil  contained  an  abundance  of  limestone,  but  no 
organic  matter  was  provided  except  the  little  in  the  stubble  and  roots  of  the 
wheat  plants. 

On  another  field  at  Rothamsted  the  average  yield  of  barley  for  60  years 
(1852  to  1911)  has  been  14.2  bushels  on  untreated  land,  38.1  bushels  where 
43  pounds  of  nitrogen  and  29  pounds  of  phosphorus  have  been  applied 
per  acre  per  annum ; while  the  further  addition  of  85  pounds  of  potassium, 
19  pounds  of  magnesium,  and  14  pounds  of  sodium  (all  in  sulfates)  raised 
the  average  yield  to  41.5  bushels,  but,  where  only  70  pounds  of  sodium  were 
applied  in  addition  to  the  nitrogen  and  phosphorus,  the  average  has  been 
43.0  bushels.  Thus,  as  an  average  of  60  years,  the  use  of  sodium  pro- 
duced 1.8  bushels  less  wheat  and  1.5  bushels  more  barley  than  the  use  of 
potassium,  with  both  grain  and  straw  removed  and  no  organic  manures 
returned. 

In  recent  years  the  effect  of  potassium  is  becoming  much  more  marked 
than  that  of  sodium  or  magnesium,  on  the  wheat  crop;  but  this  must  be 
expected  to  occur  in  time  where  no  potassium  is  returned  in  straw  or  manure, 
and  no  provision  made  for  liberating  potassium  from  the  supply  still  re- 
maining in  the  soil.  If  more  than  three-fourths  of  the  potassium  removed 
were  returned  in  the  straw  (see  Table  A),  and  if  the  decomposition  prod- 
ucts of  the  straw  have  power  to  liberate  additional  amounts  of  potassium 
from  the  soil,  the  necessity  of  purchasing  potassium  in  a good  system  of 
farming  on  such  land  is  very  remote. 

While  about  half  the  potassium,  nitrogen,  and  organic  matter,  and 
about  one-fourth  the  phosphorus  contained  in  manure  will  be  lost  by 
three  or  four  months’  exposure  in  the  ordinary  pile  in  the  barn  yard,  there 


191S ] 


McDonough  County 


45 


is  practically  no  loss  if  plenty  of  absorbent  bedding  is  used  on  cement  floors, 
and  if  the  manure  is  hauled  to  the  field  and  spread  within  a day  or  two 
after  it  is  produced.  Again,  while  the  animals  destroy  two-thirds  of  the 
organic'  matter  and  retain  one-fourth  of  the  nitrogen  and  phosphorus  in 
average  live-stock  farming,  they  retain  less  than  one-tenth  of  the  potassium, 
from  the  food  consumed ; so  that  the  actual  loss  of  potassium  in  the  products 
sold  from  the  farm,  either  in  grain  farming  or  in  live-stock  farming,  is 
wholly  negligible  on  land  containing  25,000  pounds  or  more  of  potassium 
in  the  surface  67^  inches. 

The  removal  of  one  inch  of  soil  per  century  by  surface  washing  (which 
is  likely  to  occur  wherever  there  is  satisfactory  surface  drainage  and  frequent 
cultivation)  would  permanently  maintain  the  potassium  in  grain  farming 
by  renewal  from  the  subsoil,  provided  one-third  of  the  potassium  is  removed 
by  cropping  before  the  soil  is  carried  away. 

From  all  of  these  facts  it  will  be  seen  that  the  potassium  problem  is  not 
one  of  addition  but  of  liberation;  and  the  Rothamsted  records  show  that 
for  many  years  other  soluble  salts  have  practically  the  same  power  as  po- 
tassium to  increase  crop  yields  in  the  absence  of  sufficient  decaying  organic 
matter.  Whether  this  action  relates  to  supplying  or  liberating  potassium  for 
its  own  sake,  or  to  the  power  of  the  soluble  salt  to  increase  the  availability 
of  phosphorus  or  other  elements,  is  not  known,  but  where  much  potassium 
is  removed,  as  in  the  entire  crops  at  Rothamsted,  with  no  return  of  organic 
residues,  probably  the  soluble  salt  functions  in  both  ways. 

As  an  average  of  112  separate  tests  conducted  in  1907,  1908,  1909,  and 
1910  on  the  Fairfield  experiment  field,  an  application  of  200  pounds  of 
potassium  sulfate,  containing  85  pounds  of  potassium  and  costing  $5.10,  in- 
creased the  yield  of  corn  by  9.3  bushels  per  acre:  while  600  pounds  of  kainit, 
containing  only  60  pounds  of  potassium  and  costing  $4.00,  gave  an  increase 
of  10.7  bushels.  Thus,  at  40  cents  a bushel  for  corn,  the  kainit  has  paid  for 
itself;  but  these  results,  like  those  at  Rothamsted,  were  secured  where  no 
adequate  provision  had  been  made  for  decaying  organic  matter. 

Additional  experiments  at  Fairfield  include  an  equally  complete  test  with 
potassium  sulfate  and  kainit  on  land  to  which  8 tons  per  acre  of  farm 
manure  had  been  applied.  As  an  average  of  112  tests  with  each  material, 
the  200  pounds  of  potassium  sulfate  increased  the  yield  of  corn  by  1.7  bush- 
els, while  the  600  pounds  of  kainit  also  gave  an  increase  of  1.7  bushels. 
Thus,  where  organic  manure  was  supplied,  very  little  effect  was  produced 
by  the  addition  of  either  potassium  sulfate  or  kainit ; in  part  perhaps  because 
the  potassium  removed  in  the  crops  is  mostly  returned  in  the  manure  if 
properly  cared  for,  and  perhaps  in  larger  part  because  the  decaying  organic 
matter  helps  to  liberate  and  hold  in  solution  other  plant-food  elements,  es- 
pecially phosphorus. 

In  laboratory  experiments  at  the  Illinois  Experiment  Station,  it  has  been 
shown  that  potassium  salts  and  most  other  soluble  salts  increase  the  solu- 
bility of  the  phosphorus  in  soil  and  in  rock  phosphate  as  determined  by  chem- 
ical analysis;  also  that  the  addition  of  glucose  with  rock  phosphate  in  pot- 
culture  experiments  increases  the  availability  of  the  phosphorus,  as  measured 
by  plant  growth,  altho  the  glucose  consists  only  of  carbon,  hydrogen,  and 
oxygen,  and  thus  contains  no  plant  food  of  value. 

If  we  remember  that,  as  an  average,  live  stock  destroy  two-thirds  of  the 
organic  matter  of  the  food  consumed,  it  is  easy  to  determine  from  Table  A 


46 


Soil  Report  No.  7 


[September, 


that  more  organic  matter  will  be  supplied  in  a proper  grain  system  than 
in  a strictly  live-stock  system;  and  the  evidence  thus  far  secured  from  older 
experiments  at  the  University  and  at  other  places  in  the  state  indicates  that 
if  the  corn  stalks,  straw,  clover,  etc.,  are  incorporated  with  the  soil  as  soon 
as  practicable  after  they  are  produced  (which  can  usually  be  done  in  the 
late  fall  or  early  spring),  there  is  little  or  no  difficulty  in  securing  sufficient 
decomposition  in  our  humid  climate  to  avoid  serious  interference  with  the 
capillary  movement  of  the  soil  moisture,  a common  danger  from  plowing  un- 
der too  much  coarse  manure  of  any  kind  in  the  late  spring  of  a dry  year. 

If,  however,  the  entire  produce  of  the  land  is  sold  from  the  farm,  as 
in  hay  farming,  or  when  both  grain  and  straw  are  sold,  of  course  the  draft 
on  potassium  will  then  be  so  great  that  in  time  it  must  be  renewed  by  some 
sort  of  application.  As  a rule,  such  farmers  ought  to  secure  manure  from 
town,  since  they  furnish  the  bulk  of  the  material  out  of  which  manure  is 
produced. 

Calcium-  and  Magnesium 

When  measured  by  the  actual  crop  requirements  for  plant  food,  mag- 
nesium and  calcium  are  more  limited  in  some  Illinois  soils  than  potassium. 
But  with  these  elements  we  must  also  consider  the  loss  by  leaching.  As  an 
average  of  90  analyses1  of  Illinois  well-waters  drawn  chiefly  from  glacial 
sands,  gravels,  or  till,  3 million  pounds  of  water  (about  the  average  annual 
drainage  per  acre  for  Illinois)  contained  11  pounds  of  potassium,  130  of 
magnesium,  and  330  of  calcium.  These  figures  are  very  significant,  and  it 
may  be  stated  that  if  the  plowed  soil  is  well  supplied  with  the  carbonates  of 
magnesium  and  calcium,  then  a very  considerable  proportion  of  these 
amounts  will  be  leached  from  that  stratum.  Thus  the  loss  of  calcium  from 
the  plowed  soil  of  an  acre  at  Rothamsted,  England,  where  the  soil  contains 
plenty  of  limestone,  has  averaged  more  than  300  pounds  a year  as  determined 
by  analyzing  the  soil  in  1865  and  again  in  T905.  And  practically  the  same 
amount  of’  calcium  was  found  by  analyzing  the  Rothamsted  drainage  waters. 

Common  limestone,  which  is  calcium  carbonate  (CaC03),  contains,  when 
pure,  40  percent  of  calcium,  so  that  800  pounds  of  limestone  are  equivalent 
to  320  pounds  of  calcium.  Where  10  tons  per  acre  of  ground  limestone  were 
applied  at  Edgewood,  Illinois,  the  average  annual  loss  during  the  next  ten 
years  amounted  to  790  pounds  per  acre.  The  definite  data  from  careful 
investigations  seem  to  be  ample  to  justify  the  conclusion  that  where  lime- 
stone is  needed  at  least  2 tons  per  acre  should  be  applied  every  4 or  5 years. 

It  is  of  interest  to  note  that  thirty  crops  of  clover  of  four  tons  each 
would  require  3,510  pounds  of  calcium,  while  the  most  common  prairie  land 
of  southern  Illinois  contains  only  3,420  pounds  of  total  calcium  in  the 
plowed  soil  of  an  acre.  (See  Soil  Report  No.  1.)  Thus  limestone  has  a 
positive  value  on  some  soils  for  the  plant  food  which  it  supplies,  in  addition 
to  its  value  in  correcting  soil  acidity  and  in  improving  the  physical  condi- 
tion of  the  soil.  Ordinary  limestone  (abundant  in  the  southern  and  western 
parts  of  the  state)  contains  nearly  800  pounds  of  calcium  per  ton;  while  a 
good  grade  of  dolomitic  limestone  (the  more  common  limestone  of  northern 
Illinois)  contains  about  400  pounds  of  calcium  and  300  pounds  of  mag- 
nesium per  ton.  Both  of  these  elements  are  furnished  in  readily  available 
form  in  ground  dolomitic  limestone. 


LReported  by  Doctor  Bartow  and  associates,  of  the  Illinois  State  Water  Survey. 


, Univ«i'!»;ty  cf  Illinois 

UNIVERSITY  OF  ILLINOIS 

Agricultural  Experiment  Station 


URBANA,  ILLINOIS,  OCTOBER,  1913 


SOIL  REPORT  NO.  8 


a.  MOSIER, 
. FISHER 


State  Advisory  Committee  on  Soil  Investigations 
Ralph  Allen,  Delavan  A.  N.  Abbott,  Morrison 

P.  I.  Mann,  Gilman  J.  P.  Mason,  Elgin 

C.  V.  Gregory,  538  S.  Clark  Street,  Chicago 
Agricultural  Experiment  Station  Staff  on  Soil  Investigations 
Eugene  Davenport,  Director 

Cyril  G.  Hopkins,  Chief  in  Agronomy  and  Chemistry 


Soil  Survey — 

J.  G.  Mosier,  Chief 
A.  F.  Gustafson,  Associate 
S.  V.  Holt,  Associate 
H.  W.  Stewart,  Associate 
H.  C.  Wheeler,  Associate 
F.  A.  Fisher,  Assistant 

F.  M.  W.  Wascher,  Assistant 
R.  W.  Dickenson,  Assistant 

G.  E.  Gentle,  Assistant 
0.  I.  Ellis,  Assistant 


Soil  Experiment  Fields — 

0.  S.  Fisher,  Assistant  Chief 
J.  E.  Whitchurch,  Associate 

E.  E.  Hoskins,  Associate 
^ F.  C.  Bauer,  Associate 

F.  W.  Garrett,  Assistant 
H.  C.  Gilkerson,  Assistant 

H.  F.  -T.  Fahmkopf,  Assistant 
A.  F.  Heck,  Assistant 
H.  J.  Snider,  Assistant 


Soil  Analysis — 

J.  H.  Pettit,  Chief  Soil  Biology — 

E.  Van  Alstine,  Associate  A.  L.  Whiting,  Associate 

J.  P.  Aumer,  Associate  W.  R.  Schoonover,  Assistant 

W.  H.  Sachs,  Associate 
Gertrude  Niederman,  Assistant 
W.  R.  Leighty,  Assistant 

L.  R.  Binding,  Assistant  Soils  Extension — 

C.  B.  Clevenger,  Assistant  C.  C.  Logan,  Associate 


INTRODUCTORY  NOTE 

About  two-thirds  of  Illinois  lies  in  the  corn  belt,  where  most  of  the  prairie 
lands  are  black  or  dark  brown  in  color.  In  the  southern  third  of  the  state,  the 
prairie  soils  are  largely  of  a gray  color.  This  region  is  better  known  as  the 
wheat  belt,  altho  wheat  is  often  grown  in  the  com  belt  and  com  is  also  a com- 
mon crop  in  the  wheat  belt. 

Moultrie  county,  representing  the  com  belt ; Clay  county,  which  is  fairly 
representative  of  the  wheat  belt;  and  Hardin  county,  which  is  taken  to  repre- 
sent the  unglaciated  area  of  the  extreme  southern  part  of  the  state,  were  se- 
lected for  the  first  Illinois  Soil  Reports  by  counties.  While  these  three  county 
soil  reports  were  sent  to  the  Station’s  entire  mailing  list  within  the  state,  sub- 
sequent reports  are  sent  only  to  those  on  the  mailing  list  who  are  residents  of  the 
county  concerned,  and  to  any  one  else  upon  request. 

Each  county  report  is  intended  to  be  as  nearly  complete  in  itself  as  it 
is  practicable  to  make  it,  and,  even  at- the  expense  of  some  repetition,  each 
will  contain  a general  discussion  of  important  fundamental  principles  in  order 
to  help  the  farmer  and  landowner  understand  the  meaning  of  the  soil  fer- 
tility invoice  for  the  lands  in  which  he  is  interested.  In  Soil  Report  No.  1, 
“Clay  County  Soils,”  this  discussion  serves  in  part  as  an  introduction,  while 
in  this  and  other  reports,  it  will  be  found  in  the  Appendix ; but  if  necessary  it 
should  be  read  and  studied  in  advance  of  the  report  proper. 


BOND  COUNTY  SOILS 

By  CYRIL  G.  HOPKINS,  J.  G.  MOSIER,  J.  H.  PETTIT,  and  O.  S.  FISHER 


Bond  county  is  located  nominally  in  the  lower  Illinois  glaciation,  but  much 
of  the  area,  especially  the  northwestern  part,  extends  over  the  broad  transition 
zone  between  the  lower  and  the  middle  divisions  of  the  Illinois  glaciation,  and 
for  this  reason  some  of  the  soil  types  are  rather  better  than  the  average  soils  of 
the  same  type  in  southern  Illinois. 

This  zone  seems  once  to  have  been  an  extensive  morainal  region.  Altho 
some  moraines  still  exist  as  long  ridges,  most  of  them  have  been  reduced  by 
erosion  to  rounded  hills,  so  that  only  41/4  percent  of  the  county  is  now  covered 
by  such  formation.  Other  hilly  lands,  formed  largely  by  stream  erosion,  oc- 
cupy more  than  16  percent  of  the  area. 

The  topography  of  the  more  extensive  undulating  and  level  uplands  was 
probably  produced  very  largely  by  the  influence  of  an  ice  sheet  which  once  cov- 
ered this  region.  Like  most  of  the  state,  this  county  was  overlain  by  an  ice  sheet 
during  what  is  known  as  the  Glacial  period.  During  that  period  accumulations 
of  snow  and  ice  in  parts  of  Canada  became  so  great  that  they  pushed  southward 
until  a point  was  reached  where  the  ice  melted  as  rapidly  as  it  advanced.  In 
moving  across  the  country,  the  ice  gathered  up  all  sorts  and  sizes  of  stone  and 
earthy  materials,  including  masses  of  rock,  boulders,  pebbles,  and  smaller  par- 
ticles. Some  of  these  materials  were  carried  for  hundreds  of  miles  and  rubbed 
against  the  surface  rocks  or  against  each  other  until  ground  into  powder.  When 
the  limit  of  advance  was  reached,  where  the  ice  largely  melted,  this  material 
would  accumulate  in  a broad  undulating  ridge,  or  moraine.  When  the  ice  melted 
away  more  rapidly  than  the  glacier  advanced,  the  terminus  of  the  glacier  would 
recede  and  leave  the  moraine  of  glacial  drift  to  mark  the  outer  limit  of  the  ice 
sheet. 

The  ice  made  many  advances  and  with  each  advance  and  recession  a 
terminal  moraine  was  formed.  These  moraines  are  now  seen  as  broad  ridges 
that  vary  from  one  to  ten  miles  in  width.  Thruout  the  state  these  advances  and 
recessions  of  the  ice  sheet  left  a system  of  terminal  moraines  (irregularly  con- 
centric with  Lake  Michigan)  having  generally  a steep  outer  slope  while  the 
inner  slope  is  longer  and  more  gradual.  (See  state  map  in  Bulletin  123.) 

The  material  transported  by  the  glacier  varied  with  the  character  of  the 
rocks  over  which  it  passed.  Granites,  limestones,  sandstones,  shales,  etc.,  were 
mixed  and  ground  up  together.  This  mixture  of  all  kinds  of  boulders,  gravel, 
sand,  silt,  and  clay  is  called  boulder  clay,  till,  glacial  drift,  or  simply  drift. 
The  grinding  and  denuding  power  of  glaciers  is  enormous.  A mass  of  ice  100 
feet  thick  exerts  a pressure  of  40  pounds  per  square  inch,  and  this  ice  sheet  may 
have  been  hundreds  of  feet  in  thickness.  The  materials  carried  and  pushed 
along  in  this  mass  of  ice,  especially  the  boulders  and  pebbles,  became  powerful 
agents  for  grinding  and  wearing  away  the  surface  over  which  the  ice  passed. 


1 


2 


Soil  Report  No.  8 


[October, 


Ridges  and  hills  were  rubbed  down,  valleys  filled,  and  surface  features  changed 
entirely. 

As  the  glacier  melted  in  its  final  recession,  the  material  carried  in  the  great 
mass  of  ice  was  deposited  somewhat  uniformly,  yet  not  entirely  so,  over  the 
intermorainal  tracts,  leaving  extensive  areas  of  level,  undulating,  or  rolling 
plains. 

The  depth  of  glacial  drift  in  Bond  county  varies  from  a few  feet  to  more 
than  200  feet,  as  shown  by  borings  for  wells  and  mines.  A thickness  of  204  feet 
was  determined  by  a boring  in  Greenville.  Leverett’s  estimate  for  the  average 
thickness  of  the  drift  in  the  county  is  85  feet. 

The  lower  Illinois  glaciation  is  characterized  by  light-colored  soils  which 
are  usually  strongly  acid,  whereas  in  the  middle  and  upper  Illinois  glaciations 
the  darker  colored  corn-belt  soils  predominate. 

Physiography 

The  highest  point  in  Bond  county,  650  feet,  is  in  section  30,  township  7 
north,  range  2 west,  while  the  lowest,  about  430  feet,  is  in  the  Kaskaskia  bot- 
toms in  the  southeast  corner  of  the  county.  This  gives  a difference  in  altitude 
of  220  feet.  The  following  are  the  altitudes  in  feet  above  sea  level  of  some  sta- 
tions and  towns : Greenville,  555  ; Hookdale,  503  ; Mulberry  Grove,  549  ; Perrion, 
517  ; Pocahontas,  498 ; Reno,  585  ; Sorento,  591 ; Stubblefield,  510 ; Smithboro, 
548  ; Tamalco,  465  ; Baden  Baden,  495 ; Old  Ripley,  540 ; Pleasant  Mound,  515. 

The  entire  county  lies  in  the  drainage  basin  of  the  Kaskaskia  or  Okaw  river, 
the  general  slope  being  from  north  to  south.  About  three-fourths  of  the  area 
is  drained  thru  Shoal  creek  and  its  tributaries  and  thence  into  the  Kaskaskia, 
while  about  one-fourth  of  the  area  along  the  east  side  is  drained  directly  into 
the  Kaskaskia  by  means  of  small  tributaries.  (Beaver  creek  is  a tributary  of 
Shoal  creek.)  The  large  streams  of  the  county  have  cut  valleys  varying  from 
25  to  125  feet  below  the  upland,  the  deeper  ones  being  in  the  northern  part  of 
the  county.  These  valleys  have  permitted  considerable  erosion  by  the  small 
tributaries,  and  as  a result  the  upland  adjacent  to  the  larger  streams  is  usually 
cut  up  into  hills  and  valleys  unsuited  to  ordinary  agriculture.  Before  the  land 
was  put  under  cultivation,  forests  had  advanced  up  the  streams  and  were  slowly 
invading  the  prairies,  thus  producing  a belt  of  timber  soil  along  the  streams. 

Soil  Material  and  Soil  Types 

The  Illinois  glacier  covered  Bond  county  and  left  a thick  mantle  of  drift, 
completely  burying  the  old  soil  that  preceded  it.  Then  a long  period  elapsed, 
during  which  a soil  known  as  the  old  Sangamon  soil  was  formed  on  the  surface 
of  this  drift.  Later  other  ice  invasions  occurred,  but  they  covered  only  the 
northern  part  of  the  state.  (See  state  map  in  Bulletin  123,  Iowan  and  Wis- 
consin glaciations.) 

These  later  ice  sheets  did  not  reach  Bond  county,  but  finely  ground  rock 
(rock  flour)  in  immense  quantities  was  carried  south  by  the  waters  from  the 
melting  ice  and  deposited  on  the  flooded  plains,  where,  when  dry,  it  was  picked 
up  by  the  wind,  carried  farther,  and  finally  deposited  on  the  surface,  burying  the 
old  Sangamon  soil1  to  a depth  of  5 to  20  feet  or  more.  This  wind-blown  material, 

’The  Sangamon  soil  may  sometimes  be  seen  in  cuts  as  a somewhat  dark  or  bluish  sticky 
clay  or  a weathered  zone  of  yellowish  or  brownish  clay. 


1918] 


Bund  County 


3 


called  loess,  is  a mixture  of  all  kinds  of  material  over  which  the  glacier  passed. 
It  may  be  recognized  as  a yellow,  fine-grained  material  naturally  free  from 
glacial  pebbles,  usually  underlain  by  the  pebble-bearing  drift. 

After  the  loessal  material  was  deposited  over  the  country,  the  surface 
stratum  became  mixed  with  more  or  less  organic  matter  and  thus  was  gradually 
changed  into  soil.  Surface  washing  has  produced  other  changes. 

The  soils  of  Bond  county  are  divided  into  the  four  following  classes : 

(1)  Upland  prairie  soils.  These  were  originally  covered  with  wild  prairie 
grasses,  the  partially  decayed  roots  of  which  have  been  the  chief  source  of  the  or- 
ganic matter.  The  flat  prairie  land,  naturally  poorly  drained,  contains  the  higher 
amount  of  organic  matter  because  the  grasses  and  roots  grew  more  luxuriantly 
there  and  were  largely  preserved  from  decay  by  the  higher  moisture  content  of 
the  soil. 

(2)  Upland  timber  soils,  including  those  zones  along  stream  courses  over 
which  forests  once  extended.  These  soils  contain  less  organic  matter  than  the 
upland  prairie  soils,  because  the  large  roots  of  dead  trees  and  the  surface  ac- 
cumulations of  leaves,  twigs,  and  fallen  trees  were  burned  by  forest  fires  or 
suffered  almost  complete  decay.  The  timber  lands  may  be  divided  roughly  into 
three  classes : the  level,  the  undulating,  and  the  hilly  areas. 

(3)  Ridge  soils,  including  those  on  morainal  ridges,  most  of  which  have 
been  forested.  They  may  be  divided  into  pervious  and  tight  (almost  impervious) . 
The  former  class  includes  some  of  the  best  soils  of  the  county,  while  the  soils 
of  the  latter  class  are  among  the  poorest. 

(4)  Bottom-land  soils,  including  the  flood  plains  along  streams. 


Table  1. — Soil  Types  op  Bond  County 


Soil 

type  No. 

Name  of  type 

Area 
in  square 
miles 

Area 
in  acres 

Percent 
of  total 
area 

330 

(a)  Upland  Prairie  Soils  (page  24) 

Gray  silt  loam  on  tight  clay 

121.49 

77  754 

32.66 

328 

Brown-gray  silt  loam  on  tight  clay 

61.49 

39  354 

16.54 

329 

Drab  silt  loam 

2.46 

1 574 

.66 

331 

Deep  gray  silt  loam 

2.19 

1 401 

.59 

325.1 

Black  silt  loam  on  clay 

2.48 

1 587 

.67 

(b)  Upland  Timber  Soils  (page  33) 

334 

Yellow-gray  silt  loam 

48.76 

31  206 

13.13 

335 

Yellow  silt  loam 

60.09 

38  458 

16.15 

332 

Light  gray  silt  loam  on  tight  clay 

16.45 

10  528 

4.42 

332.1 

White  silt  loam  on  tight  clay 

.68 

435 

.18 

235 

(c)  Eidge  Soils  (page  42) 

Yellow  silt  loam 

12.41 

7 942 

3.33 

233 

Gray-red  silt  loam  on  tight  clay 

1.44 

922 

.39 

245 

Yellow  fine  sandy  silt  loam 

1.98 

1 267 

.53 

1331 

(d)  Bottom-Land  Soils  (page  44) 

Deep  gray  silt  loam 

26.22 

16  781 

7.05 

1326 

Deep  brown  silt  loam 

13.74 

8 794 

3.70 

8 !!  ! 

Total 

371.88 

238  003 

100.00 

Table  1 shows  the  area  of  each  type  of  soil  in  the  county,  and  its  percentage 
of  the  total  area.  The  accompanying  map  shows  the  location  and  boundary  lines 
of  every  type  of  soil  in  the  county,  even  down  to  areas  of  a few  acres ; and  in 


4 


Soil  Report  No.  8 


[October, 


Table  2 are  reported  the  amounts  of  organic  carbon  (the  best  measure  of  the  or- 
ganic matter)  and  the  total  amounts  of  the  five  important  elements  of  plant  food 
contained  in  2 million  pounds  of  the  surface  soil  of  each  type  (the  plowed  soil  of 
an  acre  about  6%  inches  deep).  In  addition,  the  table  shows  the  amount  of 
limestone  present,  if  any,  or  the  soil  acidity  as  measured  by  the  amount  of  lime- 
stone required  to  neutralize  the  acidity  existing  in  the  soil.1 

THE  INVOICE  AND  INCREASE  OF  FERTILITY  IN  BOND  COUNTY 

SOILS 

Soil  Analysis 

In  order  to  avoid  confusion  in  applying  in  a practical  way  the  technical 
information  contained  in  this  report,  the  results  are  given  in  the  most  simplified 
form.  The  composition  reported  for  a given  soil  type  is,  as  a rule,  the  average 
of  many  analyses,  which,  like  most  things  in  nature,  show  more  or  less  varia- 
tion; but  for  all  practical  purposes  the  average  is  most  trustworthy  and  suf- 
ficient. (See  Bulletin  123,  which  reports  the  general  soil  survey  of  the  state, 
together  with  many  hundred  individual  analyses  of  soil  samples  representing 
twenty-five  of  the  most  important  and  most  extensive  soil  types  in  the  state.) 

The  chemical  analysis  of  a soil  gives  the  invoice  of  fertility  actually  pres-, 
ent  in  the  soil  strata  sampled  and  analyzed,  but,  as  explained  in  the  Appendix, 
the  rate  of  liberation  is  governed  by  many  factors.  Also,  as  there  stated,  prob- 
ably no  agricultural  fact  is  more  generally  known  by  farmers  and  landowners 
than  that  soils  differ  in  productive  power.  Even  tho  plowed  alike  and  at  the 
same  time,  prepared  the  same  way,  planted  the  same  day  with  the  same  kind 
of  seed,  and  cultivated  alike,  watered  by  the  same  rains  and  warmed  by  the  same 
sun,  nevertheless  the  best  acre  may  produce  twice  as  large  a crop  as  the  poorest 
acre  on  the  same  farm,  if  not,  indeed,  in  the  same  field ; and  the  fact  should  be 
repeated  and  emphasized  that  the  productive  power  of  normal  soil  in  humid  sec- 
tions depends  upon  the  stock  of  plant  food  contained  in  the  soil  and  upon  the 
rate  at  which  it  is  liberated. 

The  fact  may  be  repeated,  too,  that  crops  are  not  made  out  of  nothing. 
They  are  composed  of  ten  different  elements  of  plant  food,  every  one  of  which 
is  absolutely  essential  for  the  growth  and  formation  of  every  agricultural  plant. 
Of  these  ten  elements  of  plant  food,  only  two  (carbon  and  oxygen)  are  secured 
from  the  air  by  all  plants,  only  one  (hydrogen)  from  water,  while  seven  are 
secured  from  the  soil.  Nitrogen,  one  of  these  seven  elements  secured  from  the 
soil  by  all  plants,  may  also  be  secured  from  the  air  by  one  class  of  plants 
(legumes)  in  case  the  amount  liberated  from  the  soil  is  insufficient.  But  even 
the  leguminous  plants  (which  include  the  clovers,  peas,  beans,  alfalfa,  and 
vetches) , in  common  with  other  agricultural  plants,  secure  from  the  soil  alone  six 
elements  (phosphorus,  potassium,  magnesium,  calcium,  iron,  and  sulfur)  and 
also  utilize  the  soil  nitrogen  so  far  as  it  becomes  soluble  and  available  during 
their  period  of  growth. 

'The  figures  given  in  Table  2 (and  in  the  corresponding  tables  for  subsurface  and  sub- 
soil) are  the  averages  for  all  determinations,  with  some  exceptions  of  limestone  or  acidity 
present.  Some  soil  types,  particularly  those  which  are  subject  to  erosion,  may  vary  from 
acid  to  alkaline,  especially  in  the  subsurface  or  subsoil;  and  in  such  cases  abnormal  results 
are  discarded,  a report  of  the  normal  conditions  being  more  useful  than  any  average  of 
figures  involving  both  plus  and  minus  quantities. 


Co// 

Urj 


Sge  ct 

i, 


Ki/12  H^Z 


111  | 

If  " 

3 1 I : 
1 1 ! 

sm® 


l I.t 

3 1 % ! 

II 1 1 


I 

I f 

§ I 

1 1 i 

f I I 

I I 1 

■ ■■ 


I 


u 


i I 

I f 

I 1 

aa 


i 

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IL  SURVEY  MAP  OF  BOND  COUNTY 
OF  ILLINOIS  AGRICULTURAL  EXPERIMENT  STATION 


Bond  County 


5 


Table  A in  the  Appendix  shows  the  requirements  of  large  crops  for  the 
five  most  important  plant-food  elements  which  the  soil  must  furnish.  (Iron 
and  sulfur  are  supplied  normally  from  natural  sources  in  sufficient  abundance, 
compared  with  the  amounts  needed  by  plants,  so  that  they  are  never  known  to 
limit  the  yield  of  common  farm  crops.) 

As  already  stated,  the  data  in  Table  2 represent  the  total  amounts  of  plant- 
food  elements  found  in  2 million  pounds  of  surface  soil  in  Bond  county,  which 
corresponds  to  an  acre  about  6%  inches  deep.  This  includes  at  least  as  much  soil 
as  is  ordinarily  turned  with  the  plow,  and  represents  that  part  with  which  the 
farm  manure,  limestone,  phosphate,  or  other  fertilizer  applied  in  soil  improve- 
ment is  incorporated.  It  is  the  soil  stratum  that  must  be  depended  upon  in  large 
part  to  furnish  the  necessary  plant  food  for  the  production  of  crops,  as  will  be 
seen  from  the  information  given  in  the  Appendix.  Even  a rich  subsoil 
has  little  or  no  value  if  it  lies  beneath  a worn-out  surface,  for  the  weak,  shallow- 
rooted  plants  will  be  unable  to  reach  the  supply  of  plant  food  in  the  subsoil.  If, 
however,  the  fertility  of  the  surface  soil  is  maintained  at  a high  point,  then  the 
plants,  with  a vigorous  start  from  the  rich  surface  soil,  can  draw  upon  the  sub- 
surface and  subsoil  for  a greater  supply  of  plant  food. 

By  easy  computation  it  will  be  found  that  the  most  common  prairie  soils  of 
Bond  county  do  not  contain  in  the  plowed  soil  more  than  enough  total  nitrogen 
for  the  production  of  maximum  crops  for  twenty-two  years;  while  the  upland 
timber  soils  contain,  as  an  average,  even  less  nitrogen  than  the  prairie  land. 

With  respect  to  phosphorus,  the  condition  differs  only  in  degree,  nearly 
nine-tenths  of  the  soil  area  of  the  county  containing  no  more  of  that  element 
than  would  be  required  for  ten  crop  rotations  if  such  yields  were  secured  as  are 


Table  2. — Fertility  in  the  Soils  of  Bond  County 
Average  pounds  per  acre  in  2 million  pounds  of  surface  soil  (about  0 to  6%  inches) 


Soil 

type 

No. 

Soil  type 

Total 

organic 

carbon 

Total 

nitro- 

gen 

Total  1 
phos- 
phorus 

Total 

potas- 

sium 

Total 

magne- 

sium 

Total 

calcium 

Lime-  j 
stone 
present 

Soil 

acidity 

present 

Upland  Prairie  Soils 

330 

Gray  silt  loam  on 

tight  clay 

25  620 

2 640 

770 

27  410 

4 710 

5 200 

560 

328 

Brown-gray  silt  loam  on 

tight  clay 

29  490 

2 840 

670 

31  040 

4 590 

6 210 

100 

329 

Drab  silt  loam 

36  400 

3 640 

720 

29  780 

6 320 

7 500 

120 

331 

Deep  gray  silt  loam .... 

29  460 

2 840 

680 

24  180 

3 780 

4 040 

960 

325.1 

Black  silt  loam  on  clay. 

56  540 

4 760 

1 020 

32  540 

9 820 

15  540 

20 

Upland  Timber  Soils 


334 

Yellow-gray  silt  loam.. 

26  440 

2 530 

470 

35  500, 

5 870 

5 320 

320 

335 

Yellow  silt  loam., 

22  110 

2 068 

696 

36  024 

6 444 

5 040 

940 

332 

Light  gray  silt  loam  on 

tight  clay 

18  780 

1 760 

740 

26  980 

4 720 

4 110 

280 

332.1 

White  silt  loam  on  tight 

clay  

14  860 

1 360 

660 

30  120 

4 380 

5 400 

1 400 

Ridge  Soils 


235 

233 

245 

Yellow  silt  loam 

Gray-red  silt  loam  on 

tight  clay 

Yellow  fine  sandy  silt 
loam  

21  340 
35  700 
23  120 

1 940 
3 600 

2 650 

740 

820 

720 

38  940 
25  600 

39  040 

5 400 
7 140 
5 700 

8 240 
6 580 

9 850 

20 

400 

30 

Bottom-Land  Soils 

1331  1 

Deep  gray  silt  loam . . . . 

33  200 

3 120 

1 640 

37  240 

9 160 

7 380 

80 

1326  | 

Deep  brown  silt  loam . . | 

23  420 

2 100 

1 100 

34  480 

7 080 

9 760 

20 

Soil  Report  No.  8 


[October, 


suggested  in  Table  A of  the  Appendix.  It  will  be  seen  from  the  same  table  that 
in  the  case  of  the  cereals  about  three-fourths  of  the  phosphorus  taken  from  the 
soil  is  deposited  in  the  grain,  while  only  one-fourth  remains  in  the  straw  or 
stalks. 

On  the  other  hand,  the  potassium  is  sufficient  for  20  centuries  if  only  the 
grain  is  sold,  or  for  300  years  even  if  the  total  crops  should  be  removed  end 
nothing  returned.  The  corresponding  figures  are  about  1,200  and  300  years  for 
magnesium,  and  about  5,000  and  120  years  for  calcium.  Thus,  when  measured 
by  the  actual  crop  requirements  for  plant  food,  potassium  is  no  more  limited 
than  magnesium  and  calcium,  and,  as  explained  in  the  Appendix,  with  these 
elements  we  must  also  consider  the  fact  that  loss  by  leaching  is  far  greater  than 
by  cropping. 

These  general  statements  relating  to  the  total  quantities  of  plant  food  in 
the  plowed  soil  certainly  emphasize  the  fact  that  the  supplies  of  some  of  these 
necessary  elements  of  fertility  are  extremely  limited  when  measured  by  the  needs 
of  large  crop  yields  for  even  one  or  two  generations  of  people. 

The  variation  among  the  different  types  of  soil  in  Bond  county  with  respect 
to  their  content  of  important  plant-food  elements  is  also  very  marked.  Thus,  the 
richest  prairie  land  (black  silt  loam  on  clay)  contains  about  twice  as  much 
phosphorus  and  nitrogen  as  the  common  upland  timber  soils;  and  the  bottom 
lands  are  still  richer  in  phosphorus.  The  most  significant  facts  revealed  by  the 
investigation  of  the  Bond  county  soils  are  the  lack  of  limestone  and  the  low  phos- 
phorus content  of  the  common  upland  types,  which  cover  nearly  90  percent  of 
the  entire  county.  And  yet  both  of  these  deficiencies  can  be  overcome  at  a rela- 
tively small  expense  by  the  application  of  ground  limestone  and  fine-ground  raw 
rock  phosphate ; and,  after  these  are  provided,  clover  can  be  grown  and  nitrogen 
thus  secured  from  the  inexhaustible  supply  in  the  air.  If  the  clover  were  then 
returned  to  the  soil,  either  directly  or  in  farm  manure,  the  combined  effect  of 
limestone,  phosphorus,  and  nitrogenous  organic  matter,  with  a good  rotation  of 
crops,  would  in  time  double  or  treble  the  yield  of  wheat,  corn,  and  other  crops, 
on  most  farms. 

Until  the  supply  of  decaying  organic  matter  has  been  made  adequate,  some 
temporary  benefit  may  be  derived  from  the  use  of  a soluble  salt  or  a mixture  of 
salts,  such  as  kainit,  which  contains  both  potassium  and  magnesium  in  soluble 
form  and  also  some  common  salt  (sodium  chlorid).  About  600  pounds  per  acre 
of  kainit  applied  and  turned  under  with  the  raw  phosphate  will  help  to  dissolve 
the  phosphorus  as  well  as  furnish  available  potassium  and  magnesium,  and  for 
a few  years  such  use  of  kainit-  may  be  profitable  on  lands  deficient  in.  organic 
matter.  The  evidence  thus  far  secured,  however,  indicates  that  its  use  is  not  ab- 
solutely necessary  and  that  it  will  not  be  profitable  after  adequate  provision  is 
made  for  decaying  organic  matter,  which  contains  some  potassium  and  liberates 
additional  supplies  from  the  soil. 

Fortunately,  some  definite  field  experiments  have  already  been  conducted 
on  some  of  these  most  extensive  types  of  soil  in  the  lower  Illinois  glaciation,  as 
at  DuBois  in  Washington  county,  at  Fairfield  in  Wayne  county,  and  at  Raleigh 
in  Saline  county.  Before  considering  in  detail  the  individual  soil  types,  it  seems 
advisable  to  study  some  of  the  results  already  obtained  where  definite  systems 
of  soil  improvement  have  been  tried  out  on  some  of  these  experiment  fields  in 
different  parts  of  southern  Illinois. 


Bond  County 


7 


191S] 


Results  of  Field  Experiments  at  DuBois 

In  Tables  3 and  4 are  recorded  some  exceedingly  valuable  and  instructive 
data.  These  results  have  been  secured  by  twelve  years  of  actual  trial  on  the  most 
common  type  of  soil  in  Bond  county,  gray  silt  loam  on  tight  clay,  which  is  also 
a very  common  type  in  Washington  county,  where  the  DuBois  experiment  field 
is  located. 

Table  3. — Crop  Yields  in  Soil  Experiments,  DuBois  Field:  Not  Tile-drained 


Gray  silt  loam  on 
tight  clay;  lower 
Illinois  glaciation 

Corn 

1902 

Oats 

1903 

Wheat 

1904 

Clover 

1905 

Corn 

1906 

Oats 

1907 

Wheat 

1908 

Soy- 

beans 

1909 

Corn 

1910 

Oats 

1911 

Clover 
1912  1 

Wheat 

1913 

Soil 

o 

treatment 

Bushels  or 

tons  per  acre 

s 

applied 

lOljNone 

6.4 

9.4 

6.3 

1 1.25 

I 30.3j 

18.8 

.8 

3.5 

1 25.81 

1 13.1 

.46 

7.7 

102|Lime 

6.7 

16.2 

6.5 

1.57 

| 35.2 

28.8 

8.0 

6.7 

| 26.2 

24.1 

40 

8.7 

103 

Lime,  crop  res .... 

5.9 

18.1 

11.0 

1.78 

38.0 

38.1 

8.5 

7.2 

33.6 

31.9 

(.92) 

14.7 

104 

Lime,  phos 

13.4 

25.9 

25.0 

2.42' 

38.7 

43.8 

17.8 

8.5 

17.6 

40.9 

1.02 

21.0 

105 

Lime,  potas 

11.6 

27.5 

16.2 

2.22 

48.8, 

37.2 

14.8 

9.3 

65.6 

29.1 

.81 

16.8 

106 

Lime,  res.,  phos . . . 

9.3 

25.0 

32.7 

2.30 

32.3 

46.6 

19.8 

8.2 

30.0 

35.9 

(2.42) 

29.7 

107 

Lime,  res.,  potas. . 

6.8 

23.8 

20.2 

2.34 

43.6 

43.8 

16.5 

7.8 

67.6 

29.1 

(3.92) 

21.0 

108 

Lime,  phos.,  potas. 

12.4 

30.0 

27.5 

2.86 

48.9 

50.0 

20.8 

9.5 

73.2 

35.3 

1.34 

30.2 

109 

Lime,  res.,  phos., 

potas 

10.4 

29.1 

33.3 

2.83 

46.3 

46.6 

19.7 

7.8 

73.2 

38.8 

(3.00) 

30.2 

110 

Res.,  phos.,  potas . . 

2.0 

25.6 

27.3 

2.59 

39.9 

36.9 

10.0 

6.3 

66.8 

26.6 

(1.67) 

10.7 

Average  Increase:  Bushels  or  Tons  per  Acre 


For  lime 

.3 

6.8 

.2 

.32 

4.9 

10.0 

7.2 

3.2 

.4 

11.0 

-.06 

1.0 

For  residues 

-.8 

1.9 

4.5 

.21. 

2.8 

9.3 

.5 

.5 

7.4 

7.8 

.52 

6.0 

For  phosphorus 

6.7 

9.7 

18.5 

.85 

3.5 

15.0 

9.8 

1.8 

-8.6 

16.8 

.62 

12.3 

For  potassium 

4.9 

11.3 

9.7 

| .65 

13.6 

8.4 

6.8 

2.6 

39.4 

5.0 

.41 

8.1 

For  res.,  phos. 

over  phos 

-4.1 

-.9 

7.7 

-.12 

-6.4 

2.8 

2.0 

-.3 

12.4 

-5.0 

1.40 

8.7 

For  phos.,  res. 

over  res 

3.4 

6.9 

21.7 

.52 

-5.7 

8.5 

11.3 

1.0 

-3.6 

4.0 

1.50 

15.0 

For  potas.,  res.,  phos. 
over  res.,  phos. . . 

1.1 

4.1 

.6 

.53 

14.0 

0.0 

-.1 

-.4 

43.2 

2.9 

.58 

.5 

Value  of  Crops  per  Acre- in  Twelve  Years 


1 Plot  1 

Soil  treatment  applied 

1 Total  value  of 
| twelve  crops 

Value  of 
increase 

10l|None 

$58.39 

102|Lime 

79.33 

$20.94 

103 

Lime,  residues 

100.88 

42.49 

104 

Lime,  phosphorus 

131.37 

72.98 

105 

Lime,  potassium 

133.18 

74.79 

106 

Lime,  residues,  phosphorus 

151.37 

92.98 

107 

Lime,  residues,  potassium 

156.06 

97.67 

108 

Lime,  phosphorus,  potassium 

171.32 

112.93 

109 

Lime,  residues,  phosphorus,  potassium 

180.83 

122.44 

110 

Residues,  phosphorus,  potassium 

130.23 

71.84 

Value  of  Increase  per  Acre  in  Twelve  Years 

Cost  of 
increase 

For  lime 

$20.94 

$10.00? 

For  residues 

21.55 

? 

For  phosphorus 

52.04 

30.00 

For 

residues  and  phosphorus  over  phosphorus 

20.00 

? 

For  'phosphorus  and  residues  over  residues 

For  potassium,  residues,  and  phosphorus  over  residues 

50.48 

30.00 

and  phosphorus 

29.46 

30.00 

1 Figures  in  parentheses  indicate  bushels  of  seed ; the  others,  tons  of  hay. 


Soil  Report  No.  8 


[October, 


Has  tile  drainage  been  profitable?  There  arc  120  comparisons  which  bear 
on  the  answer  to  this  question,  and  the  average  of  all  these  results  summarized 
in  terms  of  value  shows  that  the  tile  drainage  has  paid  $5.59  per  acre  in  twelve 
years,  or  47  cents  per  acre  for  each  year;  whereas  it  would  require  at  least  $1.20 
an  acre  a year  to  pay  6 percent  interest  on  the  cost  of  the  tile  drainage,  the  lines 
of  tile  being  laid  five  rods  apart  at  a cost  of  not  less  than  $20  per  acre. 


Table  4. — Crop  Yields  in  Soil  Experiments,  DuBois  Field:  Tile-drained 


Gray  silt  loam  on 
tight  clay;  lower 
Illinois  glaciation 

Corn 

1902 

Oats 

1903 

Wheat 

1904 

Clover 

1905 

Corn 

1906 

Oats 

1907 

Wheat 

1908 

Soy- 

beans 

1909 

Corn 

1910 

Oats 

1911 

Clover 

19121 

Wheat 

1913 

Soil 

treatment 

Bushels  or 

tons  per  acre 

Ph 

applied 

hi 

None 

1.4 

! 17.2 

3.3 

1.29 

32.5 

1 13.1 

4.3 

3.3 

27.4 

12.2 

.40 

6.7 

112 

Lime 

3.3 

! 17.2 

11.5 

1.72 

33.6 

| 23.8 

11.0 

6.2 

29.0 

19.4 

.66 

16.5 

113 

Lime,  crop  res. . . . 

2.7 

20.6 

9.2 

1.79 

31.7 

30.0 

14.5 

6.7 

36.6 

27.2 

(1.83) 

21.5 

114 

Lime,  phos 

6^ 

27.5 

28.3 

2.27 

29.7 

31.9 

19.2 

7.2 

22.2 

30.9 

.71 

22.8 

115 

Lime,  potas 

4.9 

27.2 

14.7 

2.16 

47.5 

46.3 

16.2 

7.8 

64.2 

26.6 

.85 

21.8 

116 

Lime,  res.,  phos.  . . 

8.0 

33.8 

31.2 

2.44 

30.5 

45.9 

19.5 

8.8 

39.4 

35.6 

(2.50) 

37.2 

117 

Lime,  res.,  potas.  . 

7.3 

27.2 

23.3 

2.52 

48.3 

39.1 

18.5 

10.2 

74.6 

32.2 

(2.75) 

28.8 

118 

Lime,  phos.,  potas. 

14.1 

25^6 

32.2 

2.95 

55.2 

44.4 

23.0 

10.3 

76.4 

33.4 

1.31 

30.8 

119 

Lime,  res.,  phos., 

potas 

10.4 

31.9 

30.5 

2.89 

51.6 

42.2 

21.3 

11.3 

75.8 

38.8 

(2.33) 

29.5 

120 

Res.,  phos.,  potas. 

4.8 

33.1 

28.2 

2.79 

50.7 

35.3 

12.0 

6.7 

65.4 

28.1 

(1.83) 

24.0 

Average  Increase : Bushels  or  Tons  per  Acre 


For  lime 

1.9 1 .0 

8.2 

.43 

1.1 

10.7 

6.7 

2.9 

1.6 

| 7.2 

.26 

9.8 

For  residues 

-.6 

3.4 

-2.3 

.07 

-1.9 

6.2 

3.5 

.5 

7.6 

7^8 

1.17 

5.0 

For  phosphorus 

3.2 

10.3 

16.8 

.55 

-3.9 

8.1 

8.2 

1.0 

-6.8 

11.5 

.05 

6.3 

For  potassium 

1.6 

10.0 

3.2 

.44 

13.9 

22.5 

5.2 

1.6 

35.2 

7.2 

.19 

5.2 

For  res.,  phos. 

over  phos 

1.5 

6.3 

2.9 

.17 

.8 

14.0 

.3 

1.6 

17.2 

4.7 

1.79 

14.4 

For  phos.,  res. 

over  res 

5.3 

13.2 

22.0 

.65 

-1.2 

15.9 

5.0 

2.1 

2.8 

8.4 

.67 

15.7 

For  potas.,  res.,  phos. 
over  res.,  phos. . . 

2.4 

-1.9 

-.7 

.45 

21.1 

-3.7 

1.8  1 

2.5 

36.4 

3.2 

-.17 

-7.7 

Value  of  Crops  per  Acre  in  Twelve  Years 


Plot! 

Soil  treatment  applied 

i Total  value  of 
| twelve  crops 

Value  of 
increase 

111 

112 

None 

$ 57.66 
88.97 

$ 31.31 

113 

114 

115 

Lime,  residues 

108.25 

121.82 

133.59 

50.59 

64.16 

75.93 

Lime,  phosphorus 

[Lime,  potassium 

116 

117 

118 

ILime,  residues,  phosphorus 

161.83 

166.36 

178.08 

104.17 

108.70 

120.42 

Lime,  residues,  potassium 

iLime,  phosphorus,  potassium 

119 

120 

[Lime,  residues,  phosphorus,  potassium 

181.63 

150.62 

123.97 

92.96 

| Residues,  phosphorus,  potassium 

Value  of  Increase  per  Acre  in  Twelve  Years 

Cost  of 
increase 

For 

For 

For 

For 

For 

For 

lime 

residues 

$31.31 

19.28 

33.85 

40.01 

53.58 

19.80 

$10.00? 

? 

30.00 

? 

30.00 

30.00 

phosphorus 

residues  and  phosphorus  over  phosphorus 

phosphorus  and  residues  over  residues 

potassium,  residues,  and  phosphorus  over  residues 
and  phosphorus 

1 Figures  in  parentheses  indicate  bushels  of  seed ; the  others  tons  of  hay. 


Bond  County 


9 


191S] 


Is  the  application  of  lime  and  phosphorus  of  benefit  on  this  type  of  soil? 
The  answer  to  this  question  is  found  in  the  fact  that  the  value  of  the  twelve  crops 
on  the  untreated  land  amounted  to  only  $58.02,  whereas  the  value  of  the  in- 
crease produced  by  lime  and  phosphorus  was  $68.58;  as  an  average  of  the  two 
series.  In  other  words,  this  treatment  has  resulted  in  an  increase  greater  than  the 
crop  produced  by  the  unaided  land,  raising  the  crop  values  from  $58.02  to 
$126.60,  counting  corn  at  35  cents  a bushel,  oats  at  30  cents,  wheat  at  70  cents, 
hay  at  $6  a ton,  clover  seed  at  $6  a bushel,  and  soybeans  at  $1  a bushel— prices 
that  are  probably  sufficiently  below  the  ten-year  average  to  provide  for  the  ex- 
pense of  application  and  of  harvesting  and  marketing  the  increase.  It  should  be 
stated,  too,  that  the  application  of  lime  and  phosphorus  has  produced  a marked 
improvement  in  the  quality  of  the  crops  (especially  in  the  wheat  and  clover),  for 
which  credit  is  not  given  in  these  values. 

The  materials  used  per  acre  in  these  experiments  were  as  follows : 5 tons  of 
slaked  burned  lime  (applied  only  at  the  beginning  of  the  experiments),  2400 
pounds  of  steamed  bone  meal  (800  pounds  for  each  four-year  rotation),  and  1200 
pounds  of  potassium  sulfate  (400  pounds  for  each  rotation).  Other  investiga- 
tions (reported  in  Circulars  110,  127,  157,  165,  and  168)  have  shown  that  ground 
natural  limestone  and  fine-ground  natural  rock  phosphate  are  more  economical 
and  profitable  forms  of  lime  and  phosphorus,  and  that  the  same  effect  produced 
by  potassium  sulfate  can  also  be  secured  at  much  less  expense  either  by  means  of 
decaying  organic  matter  (from  crop  residues,  green-manure  crops,  or  farm  ma- 
nure) , or  by  the  use  of  less  expensive  soluble  salts,  such  as  kainit,  as  shown  in 
the  Appendix.  If  ground  limestone  had  been  used  on  the  DuBois  field,  $10 
would  have  paid  for  the  full  equivalent  of  the  slaked  lime  applied,  and  allowing 
$30  for  the  bone  meal  (its  actual  cost),  we  find  that  the  increase  produced  has 
paid  for  the  materials  and  left  a net  profit  of  $2.38  per  acre  per  annum,  or  70 
percent  above  the  cost.  As  an  average  of  both  series,  lime  alone  has  paid  back 
$26.12  per  acre  in  twelve  years,  and  phosphorus  used  in  addition  to  lime  and 
crop  residues  has  paid  back  $52.03:  Furthermore,  about  one-third  of  the  lime 
applied  and  at  least  two-thirds  of  the  phosphorus  applied  still  remain  in  the  soil 
for  the  benefit  of  future  crops. 

The  potassium  (kalium)  applied  during  the  twelve  years  has  cost  $30,  and 
when  applied  in  addition  to  lime,  phosphorus,  and  crop  residues,  it  has  produced 
increases  valued  at  $24.63,  leaving  a loss  of  45  cents  per  acre  per  annum.  Further- 
more, the  potassium  removed  is  equal  to  the  total  amount  applied. 

On  five  duplicate  plots  in  the  DuBois  field  commercial  nitrogen  was  used 
either  alone  or  with  other  elements  during  the  first  three  years,  but  at  a large 
financial  loss  and  with  no  apparent  residual  effect.  Since  1907,  a system  has 
been  adopted  for  these  plots  which  supplies  both  nitrogen  and  organic  matter 
by  means  of  crop  residues.  A study  of  the  detailed  results  shows  an  increasing 
effect  from  the  organic  matter  thus  supplied.  The  value  of  the  increase  pro- 
duced by  the  crop  residues  during  the  last  rotation  (four  years)  was  $13.89  per 
acre  where  they  were  used  over  lime,  and  $22.79  where  they  were  used  over  both 
lime  and  phosphorus,  this  representing  the  average  of  the  two  series  of  plots.  The 
corresponding  figures  for  the  gross  return  from  $45  worth  of  commercial  nitro- 
gen used  during  the  first  rotation  are  $2.16  and  $4.21. 


10 


Soil  Report  No.  8 


[ October , 


101 

0 

$58.39 


102 

103 

104 

105 

106 

107 

108 

109 

110 

L 

LR 

LP 

LK 

LRP 

LRK 

LPK 

LRPK 

RPK 

$79.33 

$100.88 

$131.37 

$133.18 

$151.37 

$156.06 

$171.32 

$180.83 

$130.23 

Plate  1. — Crop  Values  for  Twelve  Years 
DuBois  Experiment  Field;  Land  Not  Tile-drained 


(L — lime  or  limestone;  R — residues;  P —phosphorus;  K=potassium,  or  kalium] 


1918 1 


Bond  County 


11 


Plate  2. — Crop  Values  for  Twelve  Years 
DuBois  Experiment  Field;  Land  Tile-drained 


(L=lime  or  limestone;  B=residues;  P=phosphorus;  K=potassium,  or  kalium) 


12 


Soil  Keport  No.  8 


[i October , 


It  should  be  kept  in  mind  that  the  first  clover  to  be  plowed  under  on  the 
DuBois  field  was  in  1912,  the  system  of  supplying  nitrogen  in  crop  residues  hav- 
ing been  practiced  only  since  1907,  and  the  clover  having  failed  in  1908  owing 
to  drouth.  The  small  soybean  crop  of  1909  furnished  but  little  straw,  and  the 
other  straw  and  corn  stalks  are  of  slow  action,  so  that  final  conclusions  cannot 
yet  be  drawn  as  to  the  benefit  of  crop  residues  when  the  system  is  fully  under 
way.  Of  course  these  organic  residues  are  provided  not  only  to  furnish  nitro- 
gen, but  also  to  aid  the  liberation  of  mineral  plant  food,  especially  potassium. 
In  this  connection  a study  of  the  effect  of  potassium  is  important. 

It  is  an  interesting  fact  that  in  aggregate  value  and  on  the  corn  crop,  po- 
tassium has  produced  thus  far  an  even  larger  benefit  than  phosphorus.  Either 
one  of  these  elements  has  paid  well  when  used  without  the  other ; whereas  neither 
has  paid  its  cost  when  used  in  addition  to  the  other. 

The  soil  type  of  the  DuBois  field  contains  in  2 million  pounds  of  surface 
soil  about  800  pounds  of  phosphorus  and  25,000  pounds  of  potassium.  After 
limestone  and  organic  matter  carrying  nitrogen  have  been  supplied,  phosphorus 
is  the  only  addition  that  is  absolutely  essential  for  the  maintenance  of  plant  food 
in  permanent  rational  systems  of  farming. 

A summary  of  the  twelve  years’  results  shows,  as  an  average  of  the  two 
series,  a crop  value  of  $58.02  per  acre  from  the  unfertilized  land,  and  increased 
values  as  follows: 


For  lime  alone  $ 26.12  or  45  percent 

For  nitrogen  and  organic  matter  over  lime 20.41  or  24  percent 

For  phosphorus  as  a further  addition 52.03  or  50  percent 

For  potassium  as  a final  addition 24.63  or  16  percent 


For  total  increase  over  untreated  land $123.19  or  212  percent 


Thus  arranged,  the  field  results  are  in  harmony  with  what  might  be  ex- 
pected from  the  chemical  composition  of  the  soil.  It  should  be  noted  that,  of  the 
$24.63  credited  to  potassium,  $13.93,  or  more  than  half,  is  due  to  its  very 
marked  effect  upon  the  corn  crop  of  1910,  when  the  corn  on  all  potassium  plots 
seemed  to  possess  unusual  power  of  resistance  against  adverse  conditions,  in- 
cluding an  attack  by  chinch  bugs.  The  com  crop  of  1906  also  showed  benefit 
from  potassium,  $6.14.  Thus  $20.07,  or  four-fifths  of  the  benefit,  was  produced 
in  two  of  the  twelve  crops.  With  the  inadequate  supply  of  active  organic  mat- 
ter thus  far  provided,  potassium  applied  without  phosphorus  seems  to  have  in- 
fluenced the  liberation  of  phosphorus  from  the  soil  itself,  so  that  the  benefit  of 
this  stimulating  action,  combined  with  the  possible  direct  benefit  of  soluble 
potassium  applied  for  its  own  sake,  has  exceeded  temporarily  the  direct  benefit 
of  applied  phosphorus.  It  must  be  plain,  however,  that  no  system  can  be  per- 
manent which  does  not  provide  for  the  application  of  phosphorus ; and  that  if 
one  desires  to  make  the  most  rapid  progress  in  the  improvement  of  such  soil, 
he  should  use  limestone,  phosphorus,  and  kainit,  until  the  supply  of  organic 
manures  becomes  sufficient  to  render  the  continued  use  of  kainit  unprofitable. 
From  the  information  given  in  the  Appendix,  it  will  be  seen  that  kainit  pro- 
duces greater  benefit  than  potassium  sulfate,  and  at  less  expense ; so  that,  while 
potassium  sulfate  in  addition  to  phosphorus  has  been  used  with  loss  on  the 
DuBois  field,  if  kainit  were  substituted  for  sulfate  it  might  add  to  the  total 
profits,  at  least  until  the  soil  could  be  well  filled  with  active  organic  matter  from 
crop  residues  or  farm  manure. 


191S ] 


Bond  County 


13 


The  beneficial  effect  of  soluble  potassium  where  no  phosphorus  has  been 
added,  over  a period  of  twelve  years,  on  the  DuBois  field,  and  the  fact  that 
sodium,  an  element  which  has  no  value  as  plant  food,  produced  exactly  the  same 
increase  as  potassium  over  a period  of  twice  twelve  years  on  Broadbalk  field  at 
Rothamsted,  only  support  the  following  statement  quoted  on  page  208  of  Bulle- 
tin 123,  “The  Fertility  in  Illinois  Soils”: 

“In  considering  the  general  subject  of  culture  experiments  for  determin- 
ing fertilizer  needs,  emphasis  must  be  laid  on  the  fact  that  such  experiments 
should  never  be  accepted  as  the  sole  guide  in  determining  future  agricultural 
practice.  If  the  culture  experiments  and  the  ultimate  chemical  analysis  of  the 
soil  agree  in  the  deficiency  of  any  plant-food  element,  then  the  information  is 
conclusive  and  final ; but  if  these  two  sources  of  information  disagree,  then  the 
culture  experiments  should  be  considered  as  tentative  and  likely  to  give  way 
with  increasing  knowledge  and  improved  methods  to  the  information  based  on 
chemical  analysis,  which  is  absolute.”1 

Results  of  Field  Experiments  at  Fairfield 

The  Fairfield  experiment  field  is  divided  into  four  tracts  of  ten  acres  each, 
and  cultivated  in  a four-year  rotation,  consisting  of  corn,  cowpeas  or  soybeans, 
wheat,  and  clover.  If  the  clover  fails,  cowpeas  or  soybeans  may  be  substituted 
for  that  season ; if  the  winter  wheat  fails,  oats  may  be  substituted  in  the  spring. 

One  half  of  the  field,  or  twenty  acres,  is  tile-drained,  while  the  other  half 
has  only  the  ordinary  surface  drainage  as  commonly  provided  by  plowing  in 
rather  narrow  lands  and  keeping  the  middle  furrows  open.  On  both  the  tiled 
and  the  untiled  land  grain  farming  is  practiced  on  one  half  and  live-stock  farm- 
ing on  the  other  half.  A part  of  each  of  these  divisions  is  treated  with  two  tons 
of  limestone  and  one  ton  of  fine-ground  raw  rock  phosphate,  per  acre,  every  four 
years,  while  another  part  is  not  so  treated. 

In  the  system  of  grain  farming,  all  produce  except  the  grain  or  seed  is  re- 
turned to  the  land,  while  in  the  live-stock  farming  all  produce  (or  its  equivalent) 
is  used  for  feed  and  bedding  and  the  manure  returned  to  the  land  in  propor- 
tion to  the  crop  yields  produced  during  the  previous  rotation.  Thus,  if  the 
land  treated  with  manure,  limestone,  and  phosphate  produces,  as  an  average 
in  one  rotation,  one-half  larger  crops  than  the  land  which  receives  manure  alone, 
then  one-half  more  manure  is  applied  to  that  land  for  the  following  rotation. 
Likewise,  in  the  grain  system,  the  clover  and  other  crop  residues  returned  are 
in  proportion  to  the  yield  produced  during  the  rotation  on  the  respective  parts 
of  the  field.  It  should  be  stated  that  during  the  first  rotation  the  manure  was 
applied  in  the  same  amount  (8  tons  per  acre)  on  all  fields  in  the  live-stock 
system. 

The  regular  plan  is  to  apply  the  phosphate  and  plow  it  under  with  manure 
or  other  organic  matter,  and  to  apply  the  limestone  immediately  after  the  ground 
is  plowed  for  wheat,  in  order  that  the  limestone  may  be  mixed  with  the  surface 
soil  in  the  preparation  of  the  seed-bed  where  clover  is  to  be  seeded  the  following 

'Taken  from  “Culture  Experiments  for  Determining  Fertilizer  Needs,”  by  C.  G.  H.  in 
Cyclopedia  of  American  Agriculture,  Volume  I,  page  475. 


14 


Soil  Report  No.  8 


[October, 


spring.  However,  the  time  and  method  of  application  are  very  secondary  mat- 
ters ; the  important  thing  is  to  get  the  limestone  and  phosphate  on  the  land  and 
well  mixed  with  the  plowed  soil,  altho  it  is  better  to  mix  one  with  the  soil  before 
applying  the  other,  because  when  applied  in  intimate  contact  with  each  other 
the  limestone  tends  temporarily  to  lessen  the  availability  of  the  phosphorus,  prob- 
ably by  immediately  neutralizing  the  nitric,  carbonic,  and  organic  acids  pro- 
duced in  the  decay  of  organic  matter. 

At  $1.25  a ton  for  limestone  and  $7.50  a ton  for  rock  phosphate,  the  cost 
of  those  materials  for  four  years  amounts  to  $10  an  acre.  After  three  or  four 
rotations,  however,  the  phosphate  applications  will  be  reduced  to  about  one-half 
ton,  which  will  reduce  the  annual  expense  to  about  $1.50  per  acre.  This  expense 
would  be  practically  covered  by  an  increase  of  4 bushels  of  corn,  iy2  bushels  of 
cowpeas  or  soybeans,  2 bushels  of  wheat,  or  14  ton  of  hay,  at  very  moderate 
prices. 

In  Tables  5,  6,  7,  and  8 are  recorded  the  crop  yields  obtained  since  experi- 
ments were  begun  on  four  different  series  of  plots  on  the  Fairfield  field.1  Only 
two  series  were  under  experiment  during  the  first  year  (1905),  and  all  the  first 
four  years  are  to  be  considered  as  preliminary,  in  part  because  of  the  impossi- 
bility of  securing  the  ordinary  benefits  of  a four-year  rotation  during  the  first 
rotation  period,  in  part  because  during  the  first  four  years,  in  the  live-stock 
system,  the  manure  was  applied  uniformly  regardless  of  crop  yields,  and,  in 
particular,  because  the  present  plan  of  returning  crop  residues  was  not  begun 
until  the  end  of  the  first  four  years,  whereas  the  use  of  manure  was  begun  the 


Plate  3. — Clover  on  Fairfield  Experiment  Field,  1910.  (The  first  crop,  shown  in  pho- 
tographs, was  clipped  and  left  on  the  land;  the  second  crop  produced  no  clover 

SEED  ON  THE  UNTREATED  LAND,  BUT  1%  BUSHELS  WERE  HARVESTED  WHERE  THE  LIMESTONE 
AND  PHOSPHATE  WERE  APPLIED  WITH  NO  POTASSIUM  SALTS) 


’Other  parts  of  this  experiment  field  are  used  for  investigations  relating  to  crop  produc- 
tion, such  as  the  testing  of  varieties. 


1913 ] Bond  County  15 

first  year  (1905)  on  Series  100,  the  second  year  (1906)  on  Series  400,  the  third 
year  (1907)  on  Series  300,  and  the  fourth  year  (1908)  on  Series  200. 

In  the  fall  and  winter  of  1905-06  a system  of  tiling  with  a good  grade  and 
a satisfactory  outlet  was  laid.  Four-inch  tiles  were  placed  only  four  rods  apart, 
the  two  lines  on  the  east  half  of  each  series  about  20  to  24  inches  deep  and  the 
two  on  the  west  half  about  36  to  40  inches  deep.  Before  the  ditches  were  filled, 
the  tile  in  Series  400  was  covered  with  about  4 inches  of  gravel,  that  in  Series 
300  with  4 inches  of  cinders,  and  that  in  Series  200  with  6 inches  of  straw.  In 
Series  100  the  tile  was  covered  with  only  the  natural  dirt.  Some  of  the  tiled 
land  of  this  field  is  more  nearly  level  than  the  untiled  land,  altho  the  entire  field 
is  what  would  be  called  level  prairie  land. 

As  an  average  of  all  results  reported  in  Tables  5,  6,  7,  and  8,  from  these 
four  series  of  plots,  the  tile  drainage  has  paid  $9.11  per  acre  in  eight  years,  or 
$1.14  per  acre  for  each  year;  whereas  it  would  require  at  least  $1.50  an  acre  a 
year  to  pay  6 percent  interest  on  the  cost  of  the  tile  drainage,  which  was  not 
less  than  $25  per  acre.  It  may  be  added,  however,  that  for  the  last  four  years 
the  average  increased  value  resulting  from  tiling  has  been  $1.80  per  acre  per 
year,  which  would  pay  a fair  rate  of  interest  on  the  investment  if  the  cost  of 
tiling  did  not  exceed  $30  per  acre. 

While  it  is  very  possible  that,  with  the  continued  use  of  clover  (the  “best 
subsoiler”)  in  the  rotation,  the  tile  drainage  may  ultimately  prove  to  be  a profit- 
able investment,  it  is  plain  that  the  first  requisites  for  the  improvement  of  this 
soil  are  limestone,  phosphorus,  and  organic  matter. 


Plate  4. — Clover  on  Fairfield  Experiment  Field,  1910.  (The  first  crop,  shown  in 

PHOTOGRAPH,  MADE  % TON  OF  FOUL  GRASS  WITH  BUT  LITTLE  CLOVER  WHERE  MANURE  ALONE 
WAS  USED,  AND  2%  TONS  OH  CLEAN  CLOVER  HAY  WHERE  THE  SAME  AMOUNT  OF  MANURE 
WAS  USED  WITH  LIMESTONE  AND  PHOSPHATE  WITH  NO  POTASSIUM  SALTS) 


Soil  Repoet  No.  8 


[October, 


| 3.9  | .4  | 10.2 

of  seed;  the  others  tons  of  hay. 


101S] 


Bond  County 


17 


Soil  Ueport  No.  8 


[October, 


1918] 


Bond  County 


19 


20 


Soil  Report  No.  8 


[October, 


As  a general  average  of  both  systems  of  farming  on  both  the  tiled  and  the 
untiled  land,  on  all  series,  the  increases  produced  by  limestone  and  phosphorus 
during  the  first  rotation  were  valued  at  $9.941  an  acre,  or  about  the  cost  of  these 
materials  delivered  at  most  railroad  stations  in  southern  Illinois.  The  values  of 
the  increases  in  the  second  rotation  averaged  $24.19,  or  nearly  two  and  one-half 
times  the  cost  of  the  second  application  of  both  limestone  and  phosphate.  These 
increases  should  be  still  further  augmented  in  the  third  rotation  because  of  the 
larger  amount  of  organic  manures  to  be  returned  to  the  better  yielding  land 
and  because  of  the  continued  positive  enrichment  of  the  soil  in  phosphorus  and 
limestone. 

During  the  first  four  years,  the  limestone  and  phosphate,  costing  $10,  pro- 
duced a gain  valued  at  $7.42  when  applied  without  organic  matter,  and  a gain  of 
$12.46  when  applied  with  farm  manure;  and  during  the  second  four  years  the 
increases  due  to  $10  worth  of  limestone  and  phosphate  were  valued  at  $19.44 
when  applied  with  crop  residues  and  $28.93  when  applied  with  farm  manure. 
By  referring  to  the  Appendix  (page  57),  it  will  be  seen  that  on  the  Fairfield 
field  potassium  salts  have  produced  almost  no  effect  when  used  in  connection  with 
farm  manure;  whereas  the  largest  effect  thus  far  secured  from  limestone  and 
phosphate  has  been  obtained  where  these  materials  are  applied  with  farm  ma- 
nure. It  will  be  noted,  however,  that  their  effect  was  greater  with  crop  residues 
during  the  second  rotation  than  with  farm  manure  during  the  first.  Since  the 
use  of  crop  residues  in  these  experiments  was  not  begun  until  four  years  after 
the  first  application  of  manure,  no  conclusion  is  justified  as  to  whether  the  resi- 
due system  or  the  manure  system  will  ultimately  prove  best  for  this  soil.  The 
important  thing  is  that  the  soil  can  be  profitably  enriched  by  either.  A cross 
comparison  of  the  average  crop  values  of  the  four  series  of  plots  shows  the  value 
of  four  crops  as  $25.41  with  the  use  of  farm  manure  and  $24.18  with  the  use  of 
crop  residues,  and  perhaps  this  is  reasonably  trustworthy.  Where  limestone  and 

Table  9. — Crop  Values  per  Acre,  Fairfield  Experiment  Field 


First  Rotation:  Average  of  Four  Series 


Soil  treatment 

None 

Farm  manure 

Limestone 

Phosphate 

Farm  manure 
Limestone 
Phosphate 

Value  of  four  crops 

$20.84 

$25.41 

$28.26 

$37.87 

Second  Rotation:  Average  of  Four  Series 


Soil  treatment 

Farm  manure 

Crop  residues 
Limestone 
Phosphate 

Farm  manure 
Limestone 
Phosphate 

Value  of  four  crops 

, . . 1 $24.18 

$29.51 

$43.62 

$58.45 

'Attention  is  here  called  to  the  fact  reported  in  the  Appendix  (page  57)  that  at  Fair- 
field  where  potassium  salts  are  applied  to  one  half  of  the  land  under  experiment  they  produce 
practically  no  effect  on  the  manured  land,  while  the  effect  is  very  appreciable  on  the  unmanured 
land.  Altho  the  potassium  salts  are  applied  to  one  half  of  the  check  plots  the  same  as  to  one 
half  of  the  land  receiving  limestone  and  phosphorus,  so  that  the  $9.94  is  the  actual  increase 
produced  by  the  limestone  and  phosphorus  above  the  return  from  the  land  otherwise  treated 
the  same,  nevertheless  there  is  a possibility  that  on  part  of  the  land  represented  in  this  result 
the  effect  of  the  potassium  salts  was  different  where  used  with  limestone  and  phosphorus  than 
where  used  alone.  No  potassium  salts  had  been  applied  to  the  land  where  the  accompanying 
photographs  were  taken. 


1913 ] 


Bond  Coonty 


21 


phosphate  are  also  used,  the  corresponding  values  are  $37.87  with  manure  and 
$43.62  with  residues,  but  this  is  not  a fair  comparison  because  the  last  value 
($43.62)  was  secured  where  two  applications  of  limestone  and  phosphate  had 
been  made  (see  Table  9). 

In  Table  9 are  summarized  concisely  the  results  of  the  eight  years’  work. 
When  considered  in  relation  to  the  possible  profitable  improvement  of  the  most 
extensive  soil  type  in  Bond  county,  the  importance  of  these  figures  can  scarcely 
be  estimated.  It  should  be  remembered,  too,  that  this  soil  is  also  the  most  com- 
mon type  in  about  twenty  counties  in  southern  Illinois. 

Here  we  have  untreated,  well-rotated  land  producing  $20.84  per  acre  in 
four  years ; while  $58.45  is  the  value  at  the  same  prices  for  the  same  four  crops 
on  land  receiving  three  natural  fertilizers — farm  manure,  ground  limestone,  and 
fine-ground  raw  rock  phosphate.  If  it  costs  $5  an  acre  a year  to  farm  the  un- 


0 M LP  MLP  R M RLP  MLP 

$20.84  $25.41  $28.26  $37.87  $24.18  $29.51  $43.62  $58.45 

First  Rotation  Second  Rotation 

Plate  5. — Crop  Values  for  Four  Years  Fairfield  Experiment  Field 

(L=lime  or  limestone;  R=residues;  P=phosphorus;  K=rpotassium,  or  kalium; 
N=nitrogen ; M=manure) 


22 


Soil  Report  No.  8 


[October, 


treated  land,  only  21  cents  remains  to  pay  the  taxes,  with  nothing  for  interest ; 
moreover,  the  practice  of  leaving  land  untreated  means  a gradual  soil  depletion, 
which  leads  only  to  future  poverty  and  ruin.  If  the  land  would  sell  at  $50  an 
acre  and  if  money  is  worth  5 percent,  then  there  is  essentially  an  annual  expense 
of  $2.50  an  acre  for  which  there  is  no  return ; but  if  $2.50  per  acre  per  annum  is 
invested  in  limestone  and  phosphate  in  a rational  system  of  farming,  it  pays  back 
an  average  of  100  percent  during  the  first  rotation,  and  of  194  to  289  percent  dur- 
ing the  second  rotation;  and  this  is  in  addition  to  the  returns  from  the  crop 
residues  and  farm  manure.  Moreover,  this  is  a system  of  positive  soil  enrich- 
ment which  leads  to  the  protection  of  property  and  to  prosperity. 

The  crop  residues  include  the  corn  stalks,  straw  from  wheat  or  oats  and 
from  soybeans  or  cowpeas,  cover  crops,  and  all  clover  except  the  seed.  In  the 
live-stock  system  as  many  tons  of  fresh  manure  are  applied  to  the  land  as  the 
average  number  of  tons  of  air-dry  produce  taken  off  in  crops  during  the  previous 
rotation — an  amount  easily  produced  by  using  the  crops  for  feed  and  bedding. 

The  prices  used  in  all  these  computations  are  35  cents  a bushel  for  corn,  30 
cents  for  oats,  70  cents  for  wheat,  $1  for  soybeans  and  cowpeas,  $6  for  clover 
seed,  and  $6  a ton  for  hay.  These  prices  are  stated  conservatively  in  order  to 
avoid  any  possible  exaggeration.  If  higher  prices  were  used,  the  computed  re- 
turns from  the  land  and  treatment  would  of  course  be  increased  accordingly.  In 
some  localities  the  expense  of  hauling  will  be  greater  than  in  others ; but  it  is 
believed  that  the  prices  used  provide  ample  margin  for  average  conditions.  The 
data  are  reported  in  detail  so  that  any  one  can  make  other  computations  if  de- 
sired. 

Results  from  some  other  field  experiments  are  recorded  in  connection  with 
the  description  of  individual  soil  types. 

The  Subsurface  and  Subsoil 

In  Tables  10  and  11  are  recorded  the  amounts  of  plant  food  in  the  sub- 
surface and  the  subsoil  of  Bond  county.  It  should  be  remembered  that  these 
supplies  are  of  little  value  unless  the  top  soil  is  kept  rich.  Probably  the  most 
important  information  contained  in  these  tables  is  that  the  common  soils  of  the 
county  are  much  more  strongly  acid  in  the  subsurface  and  the  subsoil  than  in 
the  surface.  This  emphasizes  the  importance  of  having  plenty  of  limestone  in 
the  surface  to  neutralize  the  acid  moisture  which  rises  from  the  lower  strata  by 
capillary  action  during  periods  of  partial  drouth,  which  are  critical  periods  in 
the  life  of  such  plants  as  clover.  Thus,  while  the  deep  brown  silt  loam  bottom- 
land and  the  black  silt  loam  on  clay  of  the  prairie  are  practically  neutral,  the 
vast  areas  of  the  common  soils  of  the  county  are  greatly  in  need  of  limestone; 
and,  as  already  explained,  the  extensive  upland  soils  are  markedly  in  need  of 
phosphorus  and  nitrogen. 


191S ] 


Bond  County 


23 


Table  10. — Fertility  in  the  Soils  op  Bond  County 
Average  pounds  per  acre  in  4 million  pounds  of  subsurface  soil  (about  6%  to  20  inches) 


Soil 

type 

No. 

Soil  type 

Total 

organic 

carbon 

Total 

nitro- 

gen 

Total 

phos- 

phorus 

Total 

potas- 

sium 

Total 

magne- 

sium 

Total 
cal- 
| cium 

Lime- 

stone 

present 

Soil 

acidity 

present 

Upland  Prairie  Soils 

330 

Gray  silt  loam  on  tight  clay 

26  100 

2 990 

1 530 

57  540 

10  970 

9 500 

~3~m 

328 

Brown-gray  silt  loam  on 

tight  clay  

26  460 

2 700 

1 740 

63  820 

10  160 

10  400 

300 

329 

Drab  silt  loam 

43  400 

4 160 

2 040 

61  560 

12  120 

15  800 

280 

331 

Deep  gray  silt  loam 

27  720 

3 200 

1 080 

53  800 

7 800 

9 600 

5 600 

325.1 

Black  silt  loam  on  clay 

91  680 

7 320 

1 880 

63  120 

20  600 

31  160 

40 

Upland  Timber  Soils 


334 

Yellow -gray  silt  loam 

21  240 | 2 600 

1 340 

75  500 

14  620 

8 520 

5 200 

335 

Yellow  silt  loam 

16  980  2 120 

1 270 

73  820 

15  400 

8 570 

4 080 

332 

Light  gray  silt  loam  on 

tight  clay  

11  560  1 400 

1 260 

60  160 

14  260 

7 320 

10  020 

332.] 

White  silt  loam  on  tight  clay 

7 960| 1 000 

1 480 

61  400 

11  560 

10  080 

960 

Kidge  Soils 


| Yellow  silt  loam 

15  520 

2 080 

1 000 

82  400 

12  960 

13  840 

Grey -red  silt  loam  on  tight 

clay  

44  960 

4 800 

1 440 

54  000 

24  240 

12  760 

Yellow  fine  sandy  silt  loam 

18  520 

2 340 

1 620 

79  900 

18  280 

11  100 

Bottom-Land  Soils 


1331 

Deep  gray  silt  loam : 23  480 

2 720 

2 200 

74  000 

16  080110  280 

1 4 320 

1326 

Deep  brown  silt  loam 1 30  200 

• 2 880 

1 800 

69  040 

14  120 114  600, 

I 160 

Table  11. — Fertility  in  the  Soils  op  Bond  County 


Average  pounds  per  acre  in  6 million  pounds  of  subsoil  (about  20  to  40  inches) 


Soil 

1 Total  i Total  1 Total  1 

Total 

1 Total 

Total 

Lime- 

Soil 

type 

Soil  type 

organic  nitro-  phos- 

potas- 

magne- 

cal- 

stone 

acidity 

No. 

| carbon  gen  |phorus| 

sium 

| sium 

cium 

present 

present 

Upland  Prairie  Soils 


330 

Gray  silt  loam  on  tight 

1 

clay  

27  900 

3 340 

2 850 

88  940 

36  180  21  210 

2 050 

328 

Brown-gray  silt  loam  on 

tight  clay 

19  650 

2 760 

2 520 

97  290 

35  730  31  830 

often 

329 

Drab  silt  loam 

3 720 

3 180 

89  580 

27  300  22  860 

540 

331 

Deep  gray  silt  loam 

37  920 

3 720 

2 280 

79  560 

31  620  15  600 

18  300 

325.1 

Black  silt  loam  on  clay. . . 

34  920 

3 060 

2 760 

94  260 

37  620  39  840 

120 

Upland  Timber  Soils 


334 

Yellow-gray  silt  loam 

16  260 

2 190 

2 580 

118  140 

31  470 

18  030 

1 12  540 

335 

Yellow  silt  loam 

12  790 

2 170 

2 090 

105  290 

32  240 

12  910 

15  070 

332 

Light  gray  silt  loam  on 

tight  clay  

15  840 

2 070 

2 670 

96  480 

30  090 

11  460 

21  720 

332.1 

White  silt  loam  on  tight 

clay  

10  560 

1 860 

2 820 

96  540 

38  700 

18  000 

25  380 

Ridge  Soils 


235 

Yellow  silt  loam 

14  220 

2 280 

2 520 

121  260 

35  700 

21  060 

2 340 

233 

Grey-red  silt  16am  on 

tight  clay  

20  220 

2 040 

1 980 

114  600 

48  120, 

38  040 

often 

245 

Yellow  fine  sandy  silt 

loam  

21  060 

2 760 

2 960 

116  040 

37  260 

24  780 

2 010 

Bottom-Land  Soils 


1331 

Deep  gray  silt  loam ....  J 12  060 1 2 040 

3 060  108  240  26  520|  11  880 

20  100 

1326 

Deep  brown  silt  loam....1  21  540 1 2 520 

2 580  1 106  140 1 15  840  19  380 

420 

24 


Soil  Report  No.  8 


[October, 


INDIVIDUAL  SOIL  TYPES 
(a)  Upland  Prairie  Soils 

The  upland  prairie  soils  of  Bond  county  occupy  190  square  miles,  or  51 
percent  of  the  entire  area  of  the  county.  Because  of  their  larger  content  of 
organic  matter,  they  are  usually  darker  in  color  than  the  upland  timber  soils 
of  similar  topography. 

The  accumulation  of  organic  matter  in  the  prairie  soils  is  due  to  the  growth 
of  prairie  grasses  that  once  covered  them,  and  whose  network  of  roots  has  been 
protected  from  complete  decay  by  imperfect  aeration  resulting  from  the  covering 
of  fine  soil  material  and  the  moisture  it  contains.  The  tops  of  these  prairie 
grasses  contributed  little  organic  matter,  as  they  were  usually  burned  by  prairie 
fires  or  soon  became  almost  completely  decayed  from  exposure  to  the  air.  Be- 
cause of  its  great  age  and  the  loss  of  mineral  plant  food  by  leaching,  the  most 
common  prairie  soil  of  the  lower  Illinois  glaciation  has  finally  become  incapable 
of  supporting  such  a rank  vegetation  as  the  more  recently  formed  and  more 
fertile  prairies  of  the  corn  belt  in  central  and  northern  Illinois.  Consequently, 
the  southern  Illinois  prairies  are  not  so  rich  in  organic  matter  and  nitrogen  as 
the  corresponding  corn-belt  soils;  indeed,  they  differ  but  little  from  the  best 
timber  soil. 

Gray  Silt  Loam  on  Tight  Clay  (330) 

Gray  silt  loam  on  tight  clay  is  the  predominating  soil  type  in  the  lower 
Illinois  glaciation.  It  covers  121.49  square  miles  (77,754  acres),  or  32.66  percent 
of  the  area  of  the  county.  In  topography  it  is  nearly  level  or  gently  undulating, 
tho  somewhat  rolling  in  places. 

The  type  varies  primarily  in:  (1)  the  organic-matter  content;  (2)  the 
topography  and  consequent  surface  drainage;  and  (3)  the  thickness,  depth,  and 
density  of  the  tight  clay  layer  underlying  it.  Where  adjoining  the  somewhat 
rolling  areas  of  this  or  other  types,  or  in  the  vicinity  of  ridges,  this  type  has 
received  some  wash,  which  has  buried  the  tight  clay  layer  to  such  a depth  that 
it  is  less  objectionable,  and  in  such  places  the  soil  is  better  than  the  average  soil 
of  this  type.  On  the  other  hand,  where  erosion  has  been  somewhat  active,  the 
tight  layer  is  near  the  surface,  making  a very  unproductive  soil. 

This  type  contains  many  small  areas  known  as  “scalds”  or  “scald  spots,” 
readily  recognized  in  the  plowed  field  by  their  light  color.  On  these  spots  the 
ordinary  surface  soil,  and  in  many  cases  the  subsurface  soil,  is  partly  or  entirely 
absent,  leaving  the  subsoil  on  or  very  near  the  surface.  Ordinarily  these  spots 
constitute  only  a few  square  rods;  occasionally,  tho  very  rarely,  one  is  found 
covering  an  acre  or  more.  These  “scalds”  are  very  irregular  in  their  occur- 
rence, some  fields  being  almost  free  from  them  while  others  contain  many. 
Bracted  plantain  ( Plantago  aristata)  of  stunted  growth  is  a common  plant  on 
these  “scalds.” 

The  surface  stratum,  0 to  6%  inches,  is  a friable  silt  loam,  varying  in  color 
from  a light  to  a dark  gray  and  containing  sufficient  clay  to  make  it  slightly 
plastic  when  wet.  A few  small  gravels  of  quartz  and  concretions  of  hydrated 
iron  oxid  are  sometimes  found  in  it.  The  organic-matter  content  varies  from 
1.9  to  2.6  percent ; in  other  words,  from  19  to  26  tons  per  acre,  or  an  average  of 
22  tons.  The  surface  soil  is  fairly  pervious  to  water,  but  the  low  organic-matter 


1913] 


Bond  County 


25 


content,  and  the  consequent  lack  of  granulation,  renders  it  in  poor  tilth,  causing 
it  to  “run  together”  readily  with  heavy  rains  or  with  freezing  and  thawing 
when  very  wet.  The  chief  variation  in  the  surface  stratum  is  due  to  the  varia- 
tion in  the  organic-matter  content.  Analysis  shows  from  10  to  13  percent  of 
the  various  grades  of  sand  and  from  70  to  80  percent  of  silt. 

The  subsurface  stratum  varies  greatly  in  thickness.  In  many  of  the 
“scalds”  it  is  entirely  absent,  while  in  other  places  the  depth  to  the  subsoil  is 
two  feet  or  more.  The  average  thickness  is  about  13  inches.  It  contains  1.1 
percent  of  organic  matter,  and  consists  of  a silt  loam  varying  in  color  from  gray 
to  almost  white.  The  upper  part  of  the  stratum  is  sometimes  about  the  same 
color  as  the  surface  soil,  but  ordinarily  the  plow-line  marks  the  beginning  of  a 
much  lighter  colored  soil,  which  becomes  still  lighter  with  depth  and  passes  into 
a distinct  light  gray  layer  deficient  in  organic  matter,  close-grained,  very  com- 
pact when  dry,  and  very  slowly  pervious  to  water.  When  saturated,  it  is  soft, 
and  posts  may  be  driven  thru  it  readily.  A few  small  quartz  gravels  and  some 
concretions  of  hydrated  iron  oxid  are  sometimes  present. 

The  natural  subsoil  lies  at  an  average  depth  of  about  20  inches  from  the 
surface,  but  the  distance  varies  from  only  a few  inches  on  the  “scalds”  to  two 
feet  or  more  on  the  best  phase  of  the  type.  It  is  usually  made  up  of  two  distinct 
layers.  The  upper  layer,  extending  from  the  subsurface  to  an  average  depth  of 
30  to  36  inches,  consists  of  tight  clay,  sometimes  erroneously  called  ‘ ‘ hard-pan,  ’ ’ 
while  the  lower  subsoil  is  friable,  porous,  and  silty.  The  tight  clay  stratum  varies 
from  4 to  12  inches  in  thickness  and  is  usually  a close,  silty  clay,  reddish  or 
yellowish  in  color,  very  sticky  and  gummy  when  wet,  and  very  hard  when  dry. 
Water  percolates  thru  it  very  slowly. 

Because  of  the  level  topography  and  the  tight  clay  subsoil,  the  drainage  of 
this  type  is,  as  a rule,  rather  poor.  It  is  still  a question  whether  the  type  can 
be  tile-drained  profitably;  experiments  are  now  in  progress  with  the  view  of 
answering  this  question. 

The  soil  is  strongly  acid  and  low  in  nitrogen  content.  It  is  in  poor  physical 
condition;  it  “runs  together”  badly  during  rains,  is  too  compact  for  good  aera- 
tion, and  is  very -unfavorable  for  moisture  movement.  Therefore  in  the  manage- 
ment of  this  type  the  chief  essentials  are  the  application  of  limestone  and  the 
increase  of  organic-matter  content  by  every  practical  means. 

Limestone  is  needed,  not  only  to  correct  soil  acidity,  but  to  supply  calcium 
as  plant  food  as  well.  It  also  increases  granulation,  or  flocculation,  and  thus 
improves  the  tilth.  About  two  tons  per  acre  of  ground  limestone  should  be  ap- 
plied every  four  or  five  years,  and  the  initial  application  may  well  be  from  four 
to  six  tons. 

In  order  to  increase  the  organic-matter  content,  all  forms  of  vegetation,  such 
as  weeds,  manure,  straw,  corn  stalks,  etc.,  should  be  plowed  under  and  no  part 
of  them  burned.  Legume  crops,  such  as  cowpeas,  soybeans,  and  red,  alsike,  or 
sweet  clover,  should  be  grown  and  turned  back  into  the  soil,  or  fed  and  the  ma- 
nure returned.  Probably  no  crop  will  prove  better  adapted  to  adding  organic 
matter  and  nitrogen  to  the  soil  than  the  common  sweet  clover  ( Melilotus  alba), 
a deep-rooting  plant  which  will  also  help  to  loosen  the  tight  subsoil  and  make 
it  more  pervious.  In  order  to  grow  this  clover,  the  soil  must  be  sweetened  with 
ground  limestone  and  well  inoculated  with  nitrogen-fixing  bacteria. 


26 


Soil  Report  No.  8 


[October, 


This  type  is  also  markedly  deficient  in  phosphorus,  especially  for  the  grow- 
ing of  such  crops  as  wheat  and  clover;  hence  in  permanent  systems  of  improve- 
ment a liberal  use  of  phosphorus  is  essential.  This  is  applied  most  economically 
in  the  form  of  fine-ground  natural  rock  phosphate,  which  should  be  plowed  un- 
der in  intimate  contact  with  farm  manure,  clover,  or  cowpeas.  If  one-half  ton 
per  acre  is  applied  every  four  or  five  years,  the  phosphorus  content  of  the  soil 
will  be  maintained  or  slowly  increased,  but  an  application  of  one  or  two  tons 
at  one  time  gives  still  better  results.  With  the  increase  in  organic  matter,  the 
phosphorus  content  of  the  plowed  soil  should  be  raised  finally  to  at  least  2,000 
pounds  per  acre,  which  will  require  altogether  about  five  tons  of  rock  phosphate. 

This  system  of  permanent  soil  improvement  can  be  hastened,  and  sometimes 
with  profit  during  the  early  years,  by  applying  about  600  pounds  of  kainit  per 
acre  to  be  plowed  under  with  the  initial  application  of  rock  phosphate.  The 
action  of  kainit  is  explained  in  the  Appendix  (see  page  57).  If  used  at  all  it 
should  be  with  the  understanding  that  it  serves  in  part,  at  least,  as  a soil  stimu- 
lant ; and  that  when  plenty  of  decaying  organic  matter  is  provided,  the  use  of 
kainit  may  not  be  profitable.  The  benefit  derived  from  ground  limestone,  where 
a heavy  application  is  made,  seems  to  include  some  of  the  effect  of  soluble  salts 
and  to  make  the  use  of  kainit  less  important. 

For  results  of  field  experiments  on  this  soil  type,  see  Tables  3 to  9. 

Brown-Gray  Silt  Loam  on  Tight  Clay  (328) 

Brown-gray  silt  loam  on  tight  clay  covers  61.49  square  miles  (39,354  acres), 
or  16.54  percent  of  the  entire  county.  The  principal  area  is  located  between 
the  east  and  the  west  branches  of  Shoal  creek.  Other  large  areas  are  found 
near  Smithboro  and  east  of'  Stubblefield.  With  few  exceptions  the  topography 
is  flat  or  only  slightly  undulating. 

This  type  contains  many  “scalds”  where  the  subsoil  comes  to  the  surface 
or  injuriously  near  it,  usually  less  than  ten  inches.  These  “scalds”  are  very  ir- 
regular in  their  occurrence,  some  fields  being  devoid  of  them,  while  others  con- 
tain many.  They  are  indicated  by  their  lighter  color,  distinctly  seen  when  the 
ground  is  plowed. 

The  surface  soil,  0 to  6%  inches,  is  a dark  gray  to  a brown  mealy  silt  loam, 
varying  in  color  with  its  gradation  toward  other  types.  It  contains  about  2.4 
percent  of  organic  matter,  or  24  tons  per  acre.  The  amount  varies  from  2.1  to 
3 percent,  or  from  21  to  30  tons  per  acre.  The  mineral  part  of  the  soil  is  com- 
posed of  80  to  85  percent  of  the  different  grades  of  silt  with  10  to  12  percent  of 
sand,  and  some  clay.  Coarse  silt  seems  to  be  the  most  abundant  constituent.  The 
soil  is  porous,  friable,  and  easy  to  work. 

The  subsurface  stratum  varies  greatly  in  thickness  and  color.  Its  average 
thickness  is  from  10  to  12  inches,  altho  it  is  entirely  absent  in  some  places,  such 
as  “scalds,”  and  18  inches  thick  in  others.  It  consists  chiefly  of  a grayish  brown 
silt  loam,  the  color  becoming  lighter  with  depth.  Usually  there  is  a distinct 
gray  or  grayish  brown  layer  from  2 to  10  inches  thick  just  above  the  subsoil. 
Where  the  type  grades  into  gray  silt  loam  on  tight  clay  (330),  this  gray  layer 
in  some  places  becomes  quite  well  developed.  On  the  other  hand,  where  the  type 
grades  toward  brown  silt  loam  this  layer  becomes  quite  indistinct. 


19  IS ] 


Bond  County 


27 


The  subsoil  is  found  at  variable  depths,  from  only  a very  few  inches  from 
the  surface  on  the  “scalds”  to  20  inches  or  more  on  the  better  phases.  It  con- 
sists of  two  distinct  layers.  The  upper  stratum,  from  5 to  16  inches  thick,  is  a 
plastic,  gummy,  yellow,  drab  or  dark  olive-colored  clay,  very  tight  and  nearly 
impervious  to  water.  Below  it  is  a clayey  silt,  friable  and  pervious,  of  a yellow 
color,  or  yellow  with  drab  mottlings. 

The  upper  layer  of  the  subsoil  is  too  nearly  impervious  to  allow  good  drain- 
age, so  that  special  surface  drainage  in  the  form  of  dead  furrows  must  be 
provided.  Probably  the  lower,  flatter  land  of  this  type  should  be  tile-drained, 
the  lines  of  tile  being  placed  not  over  five  rods  apart.  This  opinion  is  based 
merely  upon  observation  and  reported  experience,  as  no  definite  experiments  in 
tile  drainage  have  been  conducted  on  this  type. 

In  the  improvement  of  this  type  practically  the  same  methods  should  be 
employed  as  for  the  gray  silt  loam  on  tight  clay  (330).  All  crop  residues  and 
legume  crops  not  fed  on  the  farm  should  be  turned  back  into  the  soil  in  order 
to  provide  nitrogen,  liberate  mineral  plant  food,  and  aid  in  the  physical  im- 
provement of  the  soil.  Deep-rooting  crops  should  be  grown  in  order  to  loosen 
up  the  subsoil  and  provide  more  rapid  percolation  of  water  and  air. 

This  type  contains  no  limestone,  and  is  usually  somewhat  acid.  However, 
it  is  not  so  sour  as  the  gray  silt  loam  on  tight  clay,  and  this  fact,  together  with 
the  higher  content  of  calcium  and  organic  matter  and  some  ability  to  grow 
clover  in  favorable  seasons,  has  made  it  a more  productive  soil,  generally,  than 
the  gray  prairie.  It  has  been  much  used  for  wheat,  and  possibly  because  of  the 
many  crops  removed,  this  type  in  Bond  county  is,  as  an  average,  more  deficient 
in  phosphorus  than  the  more  extensive  gray  silt  loam  on  tight  clay.  Where  it 
has  long  been  cropped  it  is  also  very  poor  in  active  organic  matter,  so  that  nitro- 
gen is  one  of  the  important  factors  which  now  limit  the  yield  of  grain  crops. 

In  Table  12  are  given  the  data  secured  from  twelve  years’  field  investiga- 
tions on  brown-gray  silt  loam  on  tight  clay,  on  the  soil  experiment  field  near 
Mascoutah,  St.  Clair  county,  which  almost  corners  Bond  county  on  the  south- 
west. These  data  are  from  a part  of  the  Mascoutah  field  where  commercial 
nitrogen,  phosphorus,  and  potassium  have  all  been  used  in  readily  available 
form  in  order  to  secure  information  as  quickly  as  possible.  The  regular  applica- 
tions per  acre  have  been  100  pounds  of  nitrogen  in  700  pounds  of  dried  blood 
every  year,  and  800  pounds  of  steamed  bone  meal  and  400  of  potassium  sulfate 
every  four  years,  corresponding  to  25  pounds  of  phosphorus  and  42  of  potassium 
for  each  year  of  the  rotation. 

At  the  time  these  experiments  were  begun  the  claim  was  commonly  made, 
especially  by  lime  manufacturers,  that  small  amounts  of  slaked  lime  should  be 
applied  frequently  to  soils.  (The  product  was  sold  under  the  name  bf 
“hydrated”  lime  at  $6  to  $10  per  ton.)  On  the  Mascoutah  field  this  material 
was  tried,  400  pounds  per  acre  in  1902  and  700  pounds  in  1903.  No  further 
applications  were  made  until  1909,  when  the  use  of  ground  limestone  was  be- 
gun. At  that  time  1 yz  tons  per  acre  was  applied,  and  four  years  later  2 tons 
per  acre  was  applied.  The  first  distinct  indication  of  benefit  from  lime  alone 
appeared  in  1913. 

Nitrogen  is  clearly  the  element  of  greatest  benefit  on  the  Mascoutah  field,  as 
shown  by  the  fact  that  the  dried  blood  has  increased  the  crop  values,  in  twelve 


28 


Soil  Report  No.  8 


f October, 


years,  from  $91.05  to  $135.50,  a gain  of  $44.45.  In  comparison,  phosphorus 
has  produced  an  increase  valued  at  $16.60,  and  potassium  an  increase  valued  at 
only  $10.63,  when  used  singly.  All  other  results  harmonize  well  with  these  val- 
ues, except  those  from  Plot  507,  which  indicate  a very  marked  influence  from 
potassium.  In  fact,  the  crop  values  from  this  plot,  which  has  received  lime,  nitro- 
gen, and  potassium,  are  $15.17  higher  than  those  from  Plot  509,  which  has  re- 
ceived lime,  nitrogen,  phosphorus,  and  potassium.  However,  nearly  $13  of  this 


Table  12. — Crop  Yields  in  Soil  Experiments,  Mascoutah  Field 


Brown-gray  silt  loam 
on  tight  clay;  middle 
Illinois  glaciation 

Corn|Corn| 
1902 j 1903 

Oats 

1904 

Wheat 

1905 

i 'orn 

1906 

Corn 

1907 

Oats 

1908 

Wheat 

1909 

Corn 

1910 

Corn 

1911 

Oats 

19121 

1 Wheat 
1913 

Soil 

o 

treatment 

Bushels  per  acre 

PM 

1 applied 

501 

None 

32  5 1 

43.4 

17.5 

1 31.7 

1 29.1 

1 8.8' 

| 20.7 

8.8 

11.6 

1 9.8 

502; 

jLime | 

32.0 1 

38.9 

22.5 

7.8 

1 30.8 

31.9 

6.6 

| 17.5 

| 8.8 

| 11.2 

[ 15.5 

503 

Lime,  nitro 1 

24.2 

47.1 

40.0 

16.7 

53.1 

45.8 

12.2 

20.8 

12.4 

19.81 

32.5 

504 

Lime,  phos 

34.4 

39.3 

68.7 

15.0 

21.6 

24.8 

9.1 

20.2 

6.8 

14.6 

14.5 

505 

Lime,  potas 

. 37.5 

47.8 

25.6 

15.7 

22.3 

32.5 

10.6 

18.0 

10.4 

17.0 1 

1 12.3 

506|Lime,  nitro.,  phos.  1 

46.1 

69.9 

44.11 

25.3 

56.7 

58.8 

28.8 

32.7 

32.4 

39.2 

33.5 

507 

Lime,  nitro.,  potas . 

59.6 

77.4 

43.1 1 

30.2 

59.6 

70.0 

37.2 

30.7 

32.0 

48.8 

27.0 

508 

Lime,  phos.,  potas.  | 

53.9 

49.0 

33.1  j 

20.0 

19.6 

38.1 

12.2 

22.3 

15.2 

19.6 

18.8 

509 

Lime,  nitro.,  phos.,  1 

1 

1 

potas 

47.8 

70.5 

37.8 

28.3 

49.6 

70.0 

30.3 

33.7 

34.4 

37.4 

28.3 

510 

Nitro.,  phos.,  potas.  j 

47.7 

52.6 

35.9 

26.3 

42.9 

65.3 

32.2 

33.7 

34.8 

28.6 

30.5 

Average  Increase:  Bushels  per  Acre 


For  nitrogen 

-7.8 

8.2 

17.5 

8.9 

22.3 

13.9 

5.6 

3.3 

3.6 

8.6 

17.0 

For  phosphorus 

2.4 

.4 

46.2 

7.2 

-9.2 

-7.1 

2.5 

2.7 

-2.0 

3.4 

-1.0 

For  potassium 

5.5 

8.9 

3.i 

7.9 

-8.5 

.6 

4.0 

.5 

1.6 

5.8 

-3.2 

For  nitro.,  phos. 

over  phos 

11.7 

30.6 

-24.6 

10.3 

35.1 

34.0 

19.7 

12.5 

25.6 

24.6 

19.0 

For  phos.,  nitro. 

over  nitro 

21.9 

22.8 

4.1 

8.6 

3.6 

13.0 

16.6 

11.9 

20.0 

19.4 

1.0 

For  potas.,  nitro.,  phos. 

over  nitro.,  phos. . 

1.7 

.6 

-6.3 

3.0 

-7.1 

11.2 

1.5 

1.0 

2.0 

-1.8 

-5.2 

Value  of  Crops  per  Acre  in  Twelve  Years 


Plot  1 

Soil  treatment  applied 

Total” value  of 
twelve  crops  j 

Value  of 
increase 

501 

502 

None 

$ 90.60 
91.05 

$ .45 

503 

504 

505 

Lime,  nitrogen 

. 135.50 
107.65 
101.68 

44.90 

17.05 

11.08 

Lime,  phosphorus 

Lime,  potassium 

506 

507 

508 

Lime,  nitrogen,  phosphorus 

Lime,  nitrogen,  potassium 

|Lime,  phosphorus,  potassium 

192.01 
207.21 
| 124.75 

101.41 

116.61 

34.15 

509 

510 

Lime,  nitrogen,  phosphorus,  potassium 

Nitrogen,  phosphorus,  potassium 

192.04 

178.95 

101.44. 

88.35 

Value  of  Increase  per  Acre  in  Twelve  Years 

Cost  of 
| increase 

For 

For 

For 

For 

For 

nitrogen 

$44.45 

16.60 

84.36 

56.51 

.03 

$180.00 

30.00 

180.00 

30.00 

30.00 

phosphorus 

nitrogen  and  phosphorus  over  phosphorus 

phosphorus  and  nitrogen  over  nitrogen 

potassium,  nitrogen,  and  phosphorus  over  nitrogen 
and  phosphorus 

The  oat  crop  failed  in  1912. 


Bond  County 


29 


1918  j 

difference  is  found  in  the  first  five  crops,  which  suggests  the  possible  influence  of 
some  unknown  factor  in  Plot  507,  such  as  the  presence  of  an  old  stack  bottom. 
But  even  if  this  abnormal  effect  during  those  years  is  disregarded,  the  data 
still  show  a slightly  greater  benefit  from  nitrogen  and  potassium  (507)  than 
from  nitrogen  and  phosphorus  (506),  altho  in  1913  a marked  superiority  of 
phosphorus  appears  in  this  comparison. 

Here  again  on  this  highest  yielding  plot  (507)  we  meet  what  seems  to  be 
the  stimulating  influence  of  the  soluble  potassium  salt.  If,  however,  the  treat- 
ment used  on  this  plot  were  practiced,  it  would  lead  ultimately  only  to  failure 
and  land  ruin,  for  it  makes  no  provision  for  the  restoration  or  the  maintenance 
of  phosphorus,  which  is  unquestionably  the  most  deficient  of  the  five  most  im- 
portant elements  of  plant  food.  The  only  guide  toward  a safe  practice  for 
permanent  systems  of  improvement  is  the  chemical  composition  of  the  soil. 

In  the  lower  part  of  Table  12  is  shown  the  influence  of  each  element  in  a 
rational  order  of  application.  From  the  composition  of  the  soil  it  is  clear  that 
both  nitrogen  and  phosphorus  must  be  supplied  for  permanent  systems  of  farm- 
ing, altho  there  may  be  some  question  as  to  which  of  these  two  is  most  needed, 
because  of  imperfect  knowledge  of  the  condition  of  the  organic  matter  and  of 
the  rate  of  decomposition  under  unknown  future  weather  conditions.  It  must 
be  plain,  however,  that  if  potassium  is  to  be  used  for  its  own  sake,  it  should 
pay  a profit  when  applied  in  addition  to  both  nitrogen  and  phosphorus. 

In  considering  these  three  elements,  nitrogen,  phosphorus,  and  potassium, 
we  find  that,  starting  with  $91.05  (the  value  of  the  crops  for  twelve  years  when 
lime  alone  was  used),  the  increases  per  acre  in  crop  values  have  been  as  follows: 

For  nitrogen  over  lime  $ 44.45 

For  phosphorus  as  a further  addition  56.51 

For  potassium  as  a final  addition ' .03 

For  total  increase  $100.99 

This  demonstration  of  more  than  doubling  crop  values  is  highly  important, 
for  it  shows  the  possibilities  of  soil  treatment;  but  of  still  more  importance  is 
the  development  of  methods  of  producing  the  same  results  with  profit  to  the 
producer.  Applied  nitrogen  has  produced  exceedingly  marked  gains,  but  never 
enough  to  pay  its  cost  in  commercial  form ; and  while  phosphorus  has  paid  nearly 
200  percent  on  the  investment  in  steamed  bone  meal  when  used  in  addition  to 
nitrogen,  the  profit  is  more  than  offset  by  the  nitrogen  deficit. 

On  another  part  of  the  Mascoutah  field,  investigations  are  in  progress 
where  nitrogen  is  secured  by  the  slower  but  less  expensive  practice  of  growing 
legumes  in  the  crop  rotation  and  returning  to  the  soil  the  crop  residues  or  farm 
manure.  In  Table  13  are  shown  for  direct  comparison  the  results  secured  where 
commercial  nitrogen  is  used  and  those  where  these  rational  means  of  securing 
nitrogen  are  employed,  both  on  lime-phosphorus  plots  and  on  plots  where  lime, 
phosphorus,  and  potassium  are  applied.  The  records  are  taken  from  the  legume 
rotation  of  the  same  crops  as  were  grown  in  identical  years  in  the  experiments 
reported  in  Table  12.  It  will  be  seen  that  the  rotations  differ  only  by  the  substi- 
tution of  a legume  crop  for  one  corn  crop.  The  final  averages,  including  duplicate 
experiments  (except  for  the  potassium),  may  be  considered  trustworthy,  within 


Soil  Report  No.  8 


[October, 


30 

rather  narrow  limits.  The  data  of  the  first  four  years  are  averaged  separately 
because  during  those  years  the  residue  and  manure  systems  were  not  well  under 
way. 

Table  13. — Crop  Yields  in  Soil  Experiments.  Mascoutah  Field 


Rotation  system 

Corn,  corn,  oats, 
and  wheat 

Corn,  oats,  wheat, 
and  clover 

Corn,  oats,  wheat, 
and  clover 

Soil  treatment 

Lime 

Nitro. 

Phos. 

Lime 

Nitro. 

Phos. 

Potas. 

Lime 

Residues 

Phos. 

Lime 

Residues 

Phos. 

Potas. 

Lime 

Manure 

Phos. 

Lime 

Manure 

Phos. 

Potas. 

1902 

Corn,  bu 

46.1 

47.8 

39.6 

45.3 

42.7 

47.1 

1903 

Corn,  bu 

69.9 

70.5 

50.8 

56.8 

43.1 

58.9 

1904 

Oats,  bu 

44.1 

37.8 

36.9 

33.4 

32.8 

39.4 

1905 

Wheat,  bu 

25.3 

28.3 

25.9 

28.2 

26.3 

31.2 

Value  of  four  crops  . . . 

$71.54 

$72.55 

| $60.84 

$65.49 

$58.28 

$70.76 

1906!Corn,  bu 

56.7 

49.6 

57.1 

57.3 

54.1 

49.1 

1907 

Corn,  bu 

58.8 

70.0 

70.0 

84.3 

73.0 

93.0 

1908  i Oats,  bu 

28.8 

30.3 

9.7 

11.3 

10.6 

13.1 

1909  Wheat,  bu 

32.7 

33.7 

32.0 

32.7 

32.7 

33.2 

1910 

Corn,  bu 

32.4 

34.4 

28.6 

36.0 

27.2 

35.2 

1911 

Corn,  bu 

39.2 

37.4 

38.2 

29.4 

29.6 

32.8 

1912 

1913 

Oats,  failed 

Wheat,  bu 

33.5 

28.3 

33.5 

34.7 

32.3 

30.2 

Value  of  eight  crops.  . . . 

$120.47  | 

$119.48 

$116.63 

$123.02 

$113.05 

$121.84 

Av.  value  of  eight  crops . 

$119.97 

$119.82 

$117.44 

Where  commercial  nitrogen  has  been  used,  the  crop  values  for  the  last  eight 
years  average  $119.97,  with  a total  cost  for  nitrogen  of  $120.00 ; but  where  crop 
residues  have  been  used  as  a source  of  nitrogen,  the  average  crop  value  is  $119.82, 
or  within  15  cents  of  that  produced  with  commercial  nitrogen.  Nearly  the  same 
results  have  been  secured  where  the  nitrogen  is  supplied  in  farm  manure  in  quan- 
tities easily  produced  from  the  crops  grown  on  the  land. 

These  data  show  that  altho  practically  the  same  aggregate  gross  values  are 
secured  with  “home-grown”  nitrogen  as  with  the  purchased  product,  the  secur- 
ing of  these  values  requires  that  the  crop  of  clover  seed  in  the  grain  system  or 
the  clover  hay  in  the  live-stock  farming  shall  bring  as  large  a return  as  the 
corn  crop  which  it  replaces.  Even  if  no  value  is  assigned  to  the  clover  crop, 
the  cost  of  the  nitrogen  secured  by  these  rational  methods  is  only  about  one- 
fourth  its  cost  in  commercial  form. 

Drab  Silt  Loam  (329) 

Some  of  the  low  and  more  poorly  surface-drained  areas  of  the  prairie  land 
have  received  deposits  of  finer  material  washed  in  from  the  slightly  higher  sur- 
rounding land,  and  in  these  places  a greater  amount  of  organic  matter  has 
accumulated,  more  particularly  in  the  surface  and  the  subsurface  strata,  owing 
to  the  more  luxuriant  growth  of  vegetation  and  the  better  conditions  for  pre- 
venting complete  decay.  This  finer  material  and  the  greater  accumulation  of 
organic  matter  have  given  rise  to  a type  of  soil,  the  drab  silt  loam  (329),  which 
is  darker  in  color,  better  in  texture,  and  somewhat  more  productive  than  the 
surrounding  gray  silt  loam  on  tight  clay  (330),  the  ordinary  prairie  land  of 
this  glaciation.  Drab  silt  loam  in  Bond  county  covers  an  area  of  2.46  square 
miles  (1,574  acres),  or  .66  percent  of  the  county. 


1913] 


Bond  County 


31 


The  surface  soil,  0 to  6%  inches,  is  a drab  to  a dark  gray.  Altho  silts 
form  the  chief  constituent,  this  stratum  always  contains  some  fine  sand  and, 
in  the  poorly  drained  areas,  enough  clay  to  give  it  some  tenacity.  The  organic 
matter  averages  3.1  percent,  or  31  tons  per  acre. 

The  subsurface  stratum  varies  from  a brownish  gray  to  a light  drab,  fre- 
quently with  blotches  of  iron  oxid.  The  amount  of  clay  varies  considerably, 
the  stratum  in  some  areas  being  very  silty,  while  in  others  it  has  sufficient  clay 
to  make  it  plastic;  in  either  case  it  is  pervious  to  water. 

The  subsoil,  20  to  40  inches  beneath  the  surface,  is  a drab  to  yellowish 
gray  silt  or  clayey  silt.  In  many  areas  the  subsoil  is  quite  heavy,  yet  sufficiently 
pervious  so  that  tile  drains  should  work  well. 

This  type  needs  underdrainage  to  bring  it  to  its  best  condition  of  tilth  and 
productiveness.  The  physical  composition,  texture,  and  structure  indicate  that 
tile  drainage  would  be  of  great  benefit,  but  actual  field  experiments  are  neces- 
sary to  determine  how  satisfactorily  tile  will  work. 

Besides  thoro  drainage,  one  of  the  most  important  points  in  the  manage- 
ment of  this  type  is  the  maintaining  or  even  the  increasing  of  the  organic  matter 
in  order  to  provide  sufficient  nitrogen  to  meet  the  needs  of  large  crops  of  corn 
and  other  non-legumes  to  be  grown  in  the  crop  rotation.  This  can  best  be  done 
by  practicing  a rotation  of  crops  in  which  a legume  is  used  as  often  as  practical 
and  by  turning  back  into  the  soil  all  crop  residues.  If  these  crops  are  fed  on 
the  farm,  the  manure  should  be  put  back  with  as  little  waste  as  possible.  This 
type  in  Bond  county  is  very  deficient  in  phosphorus  and  contains  no  limestone, 
altho  it  is  not  markedly  acid ; hence  both  phosphate  and  limestone  should  be  used. 

Deep  Gray  Silt  Loam  (331) 

Deep  gray  silt  loam  occupies  low  areas  in  the  southeastern  part  of  Bond 
county  where  silt  has  been  carried  in  from  the  higher  lands  to  such  a depth  that 
all  evidence  of  a clay  subsoil  has  been  buried  to  a depth  of  more  than  40  inches. 
It  covers  2.19  square  miles  (1,401  acres),  or  .59  percent  of  the  county. 

The  surface  soil,  0 to  6%  inches,  is  a gray  to  dark  gray  silt  loam,  changing 
in  shade  as  it  grades  into  other  types.  It  contains  2.4  percent  of  organic  matter, 
or  24  tons  per  acre. 

The  subsurface  is  a silt  loam,  lighter  in  color  than  the  surface,  and  con- 
taining 1.2  percent  of  organic  matter. 

The  subsoil  is  a gray  to  drab  silt,  differing  from  the  subsurface  in  that 
it  contains  less  organic  matter  and  has  layers  of  clay  or  clayey  silt  developed 
locally. 

The  low  organic-matter  content  of  this  type  indicates  the  necessity  of 
maintaining  or  increasing  the  supply  by  every  practical  means.  Owing  to 
the  character  of  the  subsoil,  crops  growing  on  this  type  have  a decided  ad- 
vantage over  those  on  gray  silt  loam  on  tight  clay  (330),  provided  the  subsoil 
is  thoroly  drained.  The  greater  porosity  and  deeper  feeding  range  are  of  no 
avail  when  water  is  present  in  excess. 

Among  the  prairie  soils  of  Bond  county,  this  type  is  the  most  acid  and  the 
most  deficient  in  calcium  and  magnesium;  it  is  also  very  poor  in  phosphorus. 
Phosphate  should  be  applied  liberally  in  connection  with  organic  matter; 
dolomitic  limestone  (such  as  can  be  secured  from  Grafton  and  from  most 


32 


Boil  Report  No.  8 


[October, 


northern  Illinois  deposits)  will  probably  give  even  better  results  than  the  more 
common  limestone. 


Black  Silt  Loam  on  Clay  (325.1) 

Black  silt  loam  on  clay  represents  low  prairie  land  that  was  originally 
swampy.  In  position,  this  type  corresponds  to  the  black  clay  loam  in  the 
middle  and  upper  Illinois  and  early  Wisconsin  glaciations.  In  Bond  county 
it  covers  2.48  square  miles  (1,587  acres),  or  .67  percent  of  the  county.  The 
areas  are  widely  scattered;  one  of  the  largest  is  found  south  of  Old  Ripley 
and  two  others  of  considerable  size  east  of  Greenville. 

The  surface  soil,  0 to  6%  inches,  is  a heavy  black  silt  loam  varying  in  some 
places  to  a clay  loam.  It  contains  4.9  percent  of  organic  matter,  or  49  tons 
per  acre,  an  amount  sufficient  to  make  it  quite  granular  and  keep  it  in  good 
physical  condition  if  properly  drained. 

The  subsurface  extends  15  to  18  inches  below  the  surface  soil  and  is  a dark 
clayey  silt  loam  containing  about  4 percent  of  organic  matter. 

The  subsoil  consists  of  a clay,  varying  in  color  from  dark  to  light  drab. 

The  presence  of  clay  and  organic  matter  imparts  to  this  type  of  soil  the 
property  of  shrinkage  to  a very  marked  degree,  and  in  times  of  drouth  large 
cracks  a foot  or  more  in  depth  are  formed,  which  sever  the  roots  and  damage 
the  crop  to  some  extent.  Drainage  and  good  cultivation  prevent  this  to  a con- 
siderable degree.  After  drainage,  rotation  of  crops  and  turning  under  crop 
residues  such  as  corn  stalks,  straw,  etc.,  together  with  good  tillage,  is  all  that  is 
necessary  to  keep  the  soil  in  good  physical  condition. 

This  black  silt  loam  is  by  far  the  richest  prairie  soil  in  the  county,  not 
only  in  phosphorus  and  nitrogen,  but  also  in  calcium  and  magnesium;  it  is 
somewhat  the  richest,  too,  in  potassium.  The  ratio  of  nitrogen  to  carbon  is  1 
to  12,  which  indicates  that  the  organic  matter  is  more  active  as  well  as  more 
abundant  in  this  type  than  in  the  other  prairie  types  in  Bond  county,  in  which 
the  ratio  is  only  1 to  10.  (Read  “Supply  and  Liberation  of  Plant  Food”  in 
the  Appendix.)  A liberal  use  of  phosphorus  with  clover  in  rotation  is  needed 
for  marked  improvement  in  crop  yields  on  such  soil. 

No  field  experiments  have  been  conducted  on  black  silt  loam  on  clay,  but 
its  composition  is  practically  the  same  as  the  most  extensive  soil  type  in  the 
com  belt,  the  common  brown  silt  loam.  When  well  drained  and  well  farmed 
with  a good  crop  rotation  including  clover,  phosphorus  is  the  single  factor 
which  holds  the  crop  yields  far  below  what  they  would  otherwise  be.  Thus,  on 
the  brown  silt  loam  at  the  Bloomington  soil  experiment  field,  the  values  per 
acre  of  eleven  crops  (1902-1912)  on  four  different  plots  where  no  phosphorus 
was  applied  were  $165.52  (with  lime),  $173.17  (with  lime,  crop  residues’), 
$169.66  (with  lime,  potassium),  and  $170.57  (with  lime,  residues,1  potassium)  ; 
whereas  the  corresponding  values  on  four  other  adjoining  or  intervening  plots 
whose  treatment  differed  only  by  the  addition  of  phosphorus  were  $255.44, 
$251.43,  $256.92,  and  $254.76.  Other  essentials  are  so  much  better  provided 
than  phosphorus  that  the  addition  of  this  element  paid  300  percent  on  the  in- 
vestment. 

JNo  values  are  assigned  to  crop  residues  plowed  under  until  they  reappear  in  increased 
yields  of  subsequent  crops. 


191S] 


Bond  County 


33 


(b)  Upland  Timber  Soils 

The  upland  timber  soils  of  Bond  county  aggregate  126  square  miles,  or  more 
than  one-third  of  the  area.  They  are  usually  lighter  in  color  than  the  prairie 
soils,  because  of  the  more  nearly  complete  decay  of  the  residues  of  timber 
vegetation.  In  upland  forests  these  residues  consist  of  fallen  leaves,  branches, 
and  dead  trees,  which  become  almost  completely  decomposed  thru  exposure  to 
the  oxygen  of  the  air  and  to  fungi.  Even  the  large  roots  of  trees  thru  exposure 
at  the  stump  decay  rapidly  in  the  surface  soil.  Occasional  forest  fires  help  to 
complete  the  destruction.  (As  already  explained,  the  most  common  prairie 
soil  of  the  lower  Illinois  glaciation,  because  of  its  great  age  and  the  loss  of 
mineral  plant  food  by  leaching,  has  been  reduced  in  organic-matter  content  to 
about  the  condition  of  the  undulating  timber  land.) 

Yellow-Gray  Silt  Loam  (334) 

Yellow-gray  silt  loam  in  Bond  county  covers  48.76  square  miles  (31,206 
acres),  or  13.13  percent  of  the  area  of  the  county.  It  is  found  along  the  streams 
and  generally  lies  between  the  eroded  zone  of  yellow  silt  loam  (335)  and  the 
prairie  types.  In  topography  it  is  usually  undulating,  but  it  varies  from  nearly 
level  to  quite  rolling.  The  normal  slopes  are  long  and  gentle,  but  in  places 
very  short,  abrupt  slopes  of  yellow  silt  loam  occur,  which,  are  .too  small  in  area 
to  be  shown  separately  on  the  map. 

The  surface  drainage  is  generally  good.  Erosion  takes  place  on  many 
slopes  where  no  means  are  taken  to  prevent  it.  While  this  type  was  once  gen- 
erally timbered,  it  is  also  sometimes  found  extending  into  the  prairie  along 
natural  drainage  channels,  and  as  these  particular  areas  represent  recent  erosion 
of  the  prairie,  “scalds,”  or  tight-clay  outcrops,  are  often  found,  the  presence 
of  which  renders  these  narrow  areas  very  inferior  to  the  type  as  a whole,  and  in 
some  places,  almost  worthless.  These  “scald”  areas  are  rarely  over  two  or 
three  acres  in  extent  and  more  frequently  are  only  a fraction  of  an  acre,  often 
occurring  as  narrow  strips  along  the  streams  or  draws. 

The  surface  soil,  0 to  6%  inches,  is  a yellow  to  grayish  yellow  silt  loam. 
The  freshly  plowed  surface  when  first  dry  after  a rain  takes  on  a decidedly 
grayish  appearance.  The  type  varies  to  a lighter  color  as  it  grades  into  light 
gray  silt  loam  on  tight  clay  (332),  to  a darker  color  as  it  grades  into  the  prairie 
types  (330  and  328),  and  to  a more  yellowish  color  as  it  approaches  the  yellow 
silt  loam.  It  contains  some  fine  sand,  and  locally,  in  small  areas,  quite  ap- 
preciable amounts,  but  the  principal  constituent  is  silt  of  various  grades.  The 
organic-matter  content  is  2.28  percent,  or  about  23  tons  per  acre.  The  surface 
soil  is  porous  and  friable  but  “runs  together”  badly  because  of  its  shortage  in 
organic  matter  and  lime. 

The  subsurface,  like  the  surface,  varies  from  a gray  or  yellowish  gray  to  a 
yellow  silt  loam  sufficiently  porous  to  permit  slow  percolation ; its  physical  com- 
position is  such  that  capillary  movement  takes  place  very  readily.  In  thickness 
it  varies  from  6 to  about  16  inches. 

The  subsoil  is  a yellow  or  mottled  grayish  silt  or  clayey  silt,  somewhat 
compact  but  pervious.  The  depth  to  the  natural  subsoil  is  quite  variable,  owing 
to  the  amount  of  erosion  that  has  taken  place,  but  it  commonly  varies  from  10 


34 


Soil  Report  No.  8 


[October, 


to  20  inches.  In  places,  both  surface  and  subsurface  have  been  removed,  but 
this  is  unusual. 

The  growth  of  natural  vegetation  on  this  type  has  done  very  little  toward 
adding  organic  matter.  In  fact,  it  is  more  likely  true  that  the  growth  of  forest 
trees  has  reduced  the  content  of  this  constituent  in  the  original  soil.  At  any 
rate,  this  type  is  now  deficient  in  organic  matter,  and  one  of  the  most  important 
problems  in  its  management  is  to  increase  this  constituent.  In  order  to  do  this, 
a rotation  must  be  carefully  planned,  and  all  crop  residues  and  legume  crops, 
or  their  equivalents  in  manure,  put  back  on  the  land.  Deep-rooting  crops,  such 
as  red,  mammoth,  or  sweet  clover,  should  be  grown;  but  in  order  to  grow  these 
successfully,  applications  of  ground  limestone  are  necessary.  If  the  soil  is  to 
be  enriched  and  its  productive  power  increased  and  maintained  in  any  per- 
manent way,  phosphorus  must  also  be  applied,  altho  the  application  may  well 
be  delayed  until,  thru  the  use  of  limestone  and  the  growth  of  clover,  some  or- 
ganic matter  can  be  turned  under;  or  else  kainit  should  be  applied  with  the 
phosphorus.  Very  marked  improvement  can  be  made  with  limestone  and  the 
organic  matter  which  it  helps  to  produce. 

Field  experiments  on  yellow-gray  silt  loam  in  the  lower  Illinois  glaciation 
were  begun  in  1910  in  Saline  county  near  Raleigh,  where  the  people  of  the 
community  have  provided  the  University  with  a very  suitable  tract  of  this  type 
of  soil  for  a permanent  soil  experiment  field.  There,  as  an  average  of  triplicate 
tests  each  year,  the  yield  of  corn  on  untreated  land  was  25.3  bushels  per  acre 
in  1910,  23.6  in  1911,  and  22.0  in  1912,  while  on  duplicate  plots  treated  with 
six  tons  per  acre  of  ground  limestone  and  the  limited  amount  of  organic  manures 
produced  upon  the  land,  the  corresponding  yields  were  41.4  bushels  in  1910, 
41.3  in  1911,  and  50.1  in  1912.  These  results  show  an  average  increase  of  20.6 
bushels,  of  which  only  6.6  bushels  are  due  to  organic  manures. 

As  an  average  of  duplicate  tests  with  each  crop  each  year  for  three  years, 
the  ground  limestone  increased  the  yields  by  14  bushels  of  corn,  10.55  bushels 
of  oats,  .85  ton  of  hay  (clover  or  cowpea),  and  4.45  bushels  of  wheat.  The 
value  of  these  increases  at  35  cents  for  corn,  30  cents  for  oats,  70  cents  for 
wheat,  and  $6  for  hay,  amounts  to  $16.28  and  corresponds  to  the  value  of  the 
increase  produced  by  limestone  on  one  acre  during  a four-year  rotation.  Thus 
the  limestone  paid  about  200  percent  interest  on  the  investment,  and  the  ap- 
plication of  6 tons  per  acre  is  sufficient  for  about  fifteen  years,  altho  in  order 
to  maintain  a liberal  amount  of  limestone  in  the  soil  it  is  well  to  apply  about  2 
tons  per  acre  every  four  or  five  years  after  making  the  heavier  initial 
application. 

Owing  to  the  low  supply  of  active  organic  matter  in  the  soil  at  Raleigh, 
phosphorus  produced  no  benefit,  as  an  average,  during  the  first  two  years ; but 
with  the  turning  under  of  the  crop  residues  and  farm  manure  in  proportion 
to  the  crops  produced,  the  effect  of  phosphorus  is  seen  to  some  extent  in  the 
crops  of  1912  and  1913.  The  fourth  series  of  plots  will  receive  its  first  farm 
manure  for  the  1914  crops,  so  that  trustworthy  data  as  to  the  benefits  of  orgapic 
matter,  or  of  phosphorus  combined  with  organic  matter,  will  not  be  secured 
before  the  second  rotation  period. 


1913 ] 


Bond  County 


35 


Where  kainit  has  been  used  at  the  rate  of  200  pounds  for  each  year,  ap- 
plied in  connection  with  phosphate  and  in  addition  to  the  6 tons  of  limestone, 
the  average  increase  for  the  kainit  during  the  first  three  years  has  been  $2.90, 
or  only  about  half  its  cost. 


Yellow  Silt  Loam  (335) 

Yellow  silt  loam  in  Bond  county  includes  the  broken,  very  rolling,  and  hilly 
land  along  the  streams  and  sometimes  on  the  steep  slopes  of  ridges.  It  is  best 
to  keep  much  of  it  forested,  tho  when  properly  treated  it  makes  good  pasture 
land.  It  is  so  steeply  sloping  that  little  of  it  should  ever  be  cultivated.  When 
it  is  cultivated,  the  utmost  care  should  be  taken  to  prevent  washing,  which  is 
the  most  serious  danger  to  this  type  of  soil.  Already  many  fields  have  been 
ruined  by  gullying.  This  type  of  soil  covers  an  area  of  60.09  square  miles 
(38,458  acres),  or  16.15  percent  of  the  county. 

The  surface  soil  is  a friable  yellow  silt  loam  varying  somewhat  with 
topography.  The  less  broken  areas  are  a grayish  yellow,  while  the  steep  slopes 
are  reddish  yellow,  or  brownish  yellow  where  a little  more  organic  matter  re- 
mains. As  a rule,  the  soil  contains  enough  fine  sand  to  give  it  a fairly  good  tex- 
ture, but  it  is  very  deficient  in  organic  matter,  having  only  2 percent,  or  20 
tons  per  acre.  This  condition  contributes  toward  its  excessive  washing.  ‘ ‘ Clay 
points,”  or  places  where  the  top  soil  has  been  removed  by  washing,  are  quite 
common,  and  they  are  very  unproductive. 

The  subsurface  varies  in  thickness;  where  little  or  no  washing  has  taken 
place  it  is  from  6 to  14  inches  thick.  It  consists  usually  of  a friable,  slightly 
loamy,  yellow  silt,  mottled  with  gray  or  with  reddish  blotches  of  iron  oxid. 

The  subsoil  is  usually  a somewhat  friable  and  quite  pervious,  yellow,  clayey 
silt.  Where  much  washing  has  occurred,  the  glacial  drift  frequently  forms  the 
subsoil. 

Of  most  importance  in  the  management  of  this  type  is  the  prevention  of 
much  loss  by  washing.  Erosion  occurs  as  sheet-washing  and  gullying.  Ordi- 
narily sheet-washing  is  not  thought  of  as  doing  very  much  damage,  but  it  is 
really  the  most  injurious  form  of  erosion.  Gullying  results  in  the  absolute  ruin 
of  small  areas,  but  sheet-washing  reduces  the  productive  capacity  of  large  areas 
to  such  an  extent  that  it  prevents  not  only  profitable  cropping  but  even  the 
growing  of  crops  large  enough  to  pay  for  their  raising.  Every  means  should 
be  taken  to  prevent  this  loss. 

The  steep,  gullied  slopes  probably  never  can  be  reclaimed  with  profit  for 
cropping  purposes  at  the  present  average  prices  for  labor  and  farm  produce. 
The  forests  that  originally  covered  these  lands  should  never  have  been  entirely 
removed.  The  only  thing  that  made  these  lands  valuable  in  the  first  place  was 
the  forests,  and  to  make  them  of  any  future  value  they  should  be  reforested. 
This  has  been  done  in  a few  cases  and  has  met  with  excellent  success.  The  ac- 
companying illustrations  show  such  results.  The  black  locust  can  be  used  most 
successfully  for  this  purpose,  as  it  is  largely  independent  of  the  supply  of  nitroge- 
nous organic  matter  in  the  soil,  altho  it  is  subject,  of  course,  to  insect  injury 
which  is  sometimes  fatal.  Where  not  in  forest,  the  steep  land  should  be  kept  in 
pasture  as  much  as  possible ; if  cropped,  it  should  be  for  only  one  or  two  years 


Soil  Report  No.  8 


[October, 


36 


Plate  6. — Young  Grove  of  Black  Locust  Trees  on  Rolling  Hill  Land  in  Johnson 
County,  Illinois  (Grown  by  J.  C.  B.  Heaton) 

at  a time  and  then  the  land  should  be  reseeded  for  pasture.  Live-stock  is  indis- 
pensable to  general  farming  on  this  type  of  soil. 

Sheet-washing  on  the  moderate  slopes  may  be  prevented  to  a great  extent 
by  the  following  methods: 

(1)  By  increasing  the  organic-matter  content,  thus  binding  together  the 
soil  particles  and  rendering  the  soil  more  porous.  This  can  be  done  by  apply- 
ing farm  manure  and  plowing  under  stubble,  straw,  corn  stalks,  and  legume 
crops,  such  as  clover  and  cowpeas. 

(2)  By  deep  plowing  from  seven  to  ten  inches,  in  order  to  increase  the 
absorption  of  water  and  diminish  the  run-off.  Ten  inches  of  loose  soil  will 
readily  absorb  two  inches  of  rainfall  without  run-off. 

(3)  By  contour  plowing.  When  land  is  plowed  up  and  down  the  slope, 
as  is  often  done  in  this  state,  dead  furrows  are  made  which  furnish  excellent 
beginnings  for  gullies.  Even  the  little  depressions  between  furrows  aid  in 
washing.  On  land  subject  to  serious  washing,  plowing  should  always  be  done 
across  the  slope,  on  the  contour,  so  that  water  will  stand  in  the  furrow  without 
running  in  either  direction.  Every  furrow  will  then  act  as  an  obstruction  to 
the  movement  of  water  down  the  slope,  thus  checking  the  velocity  of  the  water 


1918 ] 


Bond  County 


37 


\f;- 


Plate  7. — Grove  of  Locust  Trees  About  Twenty-five  Years  Old  on  Rolling  Hill  Land 
in  Johnson  County,  Illinois  (Grown  by  J.  C.  B.  Heaton) 


and  its  power  to  wash,  and  also  facilitating  absorption  and  diminishing  the 
amount  of  run-off. 

(4)  By  using  cover  crops  to  hold  the  soil  during  the  winter  and  spring. 
Rye  is  a fairly  good  cover  crop  to  sow  in  the  corn  during  the  late  summer  or 
early  fall.  Wheat,  especially  when  seeded  late,  is  a poor  crop  to  grow  on  rolling 
land  because  it  does  not  usually  make  sufficient  growth  in  the  fall  to  afford 
a good  protection  to  the  soil  during  winter.  Of  course  both  rye  and  wheat 
invite  the  development  of  chinch  bugs.  A mixture  of  winter  vetch  and  clover 
with  a few  cowpeas,  seeded  at  the  time  of  the  last  cultivation  of  the  corn,  gives 
good  results  in  favorable  seasons.  (See  Circular  119,  “Washing  of  Soils  and 
Methods  of  Prevention.”) 


38 


Soil  Report  No.  8 


[October, 


This  yellow  silt  loam  is  markedly  acid.  Where  cropping  is  practiced,  lime- 
stone should  be  used  liberally,  especially  for  the  benefit  of  clover  grown  to  pro- 
vide nitrogen,  in  which  this  soil  is  very  deficient,  particularly  where  it  has 
been  long  cultivated  and  thus  exposed  to  surface  washing.  On  such  land  nitro- 
gen is  the  element  which  now  first  limits  the  growth  of  grain  crops,  as  will  be 
seen  from  Plates  8 and  9 and  Tables  14  and  15. 

In  one  experiment,  a large  quantity  of  the  typical  worn  hill  soil  was  col- 
lected from  two  different  places.1  Each  lot  of  soil  was  thoroly  mixed  and  put 
in  ten  four- gallon  jars.  Ground  limestone  was  added  to  all  the  jars  except  the 
first  and  last  in  each  set,  those  two  being  retained  as  control  or  check  pots. 
The  elements  nitrogen,  phosphorus,  and  potassium  were  added  singly  and  in 
combination,  as  shown  in  Table  14. 

As  an  average,  the  nitrogen  applied  produced  a yield  about  eight  times  as 
large  as  that  secured  without  the  addition  of  nitrogen.  While  some  variations 
in  yield  are  to  be  expected,  because  of  differences  in  the  individuality  of  seed 


Plate  8. — Wheat  in  Pot-Culture  Experiment  with  Yellow  Silt  Loam  of  Worn  Hill 
Land  (See  Table  14) 

Table  14. — Crop  Yields  in  Pot-Culture  Experiment  with  Yellow  Silt  Loam  of  Worn 

Hill  Land 


(Grams  per  pot) 


Pot 

No. 

Soil  treatment  applied 

Wheat 

Oats 

1 

None 

3 

5 

2 

Limestone  

4 

4 

3 

Limestone,  nitrogen 

26 

45 

4 

Limestone,  phosphorus 

3 

6 

5 

Limestone,  potassium 

3 

5 

6 

Limestone,  nitrogen,  phosphorus 

34 

38 

7 

Limestone,  nitrogen,  potassium 

33 

46 

8 

Limestone,  phosphorus,  potassium 

2 

5 

9 

Limestone,  nitrogen,  phosphorus,  potassium 

34 

38 

10 

None 

3 

5 

Average  yield  with  nitrogen 

32 

42 

Average  yield  without  nitrogen 

3 

5 

Average  gain  for  nitrogen 

29 

37 

1Soil  for  wheat  pots  from  loess-covered  unglaciated  area,  and  that  for  oat  pots  from 
upper  Illinois  glaciation. 


191S ] 


Bond  County 


39 


or  other  uncontrolled  causes,  yet  there  is  no  doubting  the  plain  lesson  taught 
by  these  actual  trials  with  growing  plants. 

The  question  arises  next,  Where  is  the  farmer  to  secure  this  much-needed 
nitrogen?  To  purchase  it  in  commercial  fertilizer  would  cost  too  much; 
indeed,  under  average  conditions  the  cost  of  the  nitrogen  in  such  fertilizers  is 
greater  than  the  value  of  the  increase  in  crop  yields. 

There  is  no  need  whatever  to  purchase  nitrogen,  for  the  air  contains  an 
inexhaustible  supply,  which,  under  suitable  conditions,  the  farmer  can  draw 
upon,  not  only  without  cost,  but  with  profit  in  the  getting.  Clover,  alfalfa, 
cowpeas,  and  soybeans  are  not  only  worth  raising  for  their  own  sake,  but  they 
have  power  to  secure  nitrogen  from  the  atmosphere  if  the  soil  contains  lime- 
stone and  the  proper  nitrogen-fixing  bacteria. 

In  order  to  secure  further  information  along  this  line,  another  experiment 
with  pot  cultures  was  conducted  for  several  years  with  the  same  type  of  worn 
hill  soil  as  that  used  for  the  wheat  cultures  described  above.  The  results  are 
reported  in  Table  15. 

To  three  pots  (Nos.  3,  6,  and  9)  nitrogen  was  applied  in  commercial  form, 
at  an  expense  amounting  to  more  than  the  total  value  of  the  crops  produced. 
In  three  other  pots  (Nos.  2,  11,  and  12)  a crop  of  cowpeas  was  grown  during 
the  late  summer  and  fall  and  turned  under  before  the  wheat  or  oats  were 
planted.  Pots  1 and  8 served  for  important  comparisons.  After  the  second 
catch  crop  of  cowpeas  had  been  turned  under,  the  yield  from  Pot  2 exceeded 


Plate  9. — Wheat  in  Pot-Culture  Experiment  with  Yellow  Silt  Loam  of  Worn  Hill 
Land  (See  Table  15) 

Table  15. — Crop  Yields  in  Pot-Culture  Experiment  with  Yellow  Silt  Loam  of  Worn 
Hill  Land  and  Nitrogen-Fixing  Green  Manure  Crops 


(Grams  per  pot) 


Pot 

No. 

Soil  treatment 

1903 

Wheat 

1904 

Wheat 

1905 

Wheat 

1906 

Wheat 

1907 

Oats 

1 

2 

11 

12 

None  

Limestone,  legume 

Limestone,  legume,  phosphorus 

Limestone,  legume,  phosphorus,  potassium . . 

10 

14 

16 

4 

17 

19 

20 

4 

26 

■ 20 
21 

4 

19 

18 

19 

6 

37 

27 

30 

3 

Limestone,  nitrogen 

17 

14 

15 

9 

28 

6 

Limestone,  nitrogen,  phosphorus 

26 

20 

18 

18 

30 

9 

Limestone,  nitrogen,  phosphorus,  potassium. 

31 

34 

21 

20 

26 

8 

Limestone,  phosphorus,  potassium 

3 

3 

5 

3 

7 

40 


Soil  Report  No.  8 


[ October , 


that  from  Pot  3 ; and  in  the  subsequent  years  the  legume  green  manures  pro- 
duced, as  an  average,  rather  better  results  than  the  commercial  nitrogen.  This 
experiment  confirms  that  reported  in  Table  14,  in  showing  the  very  great  need 
of  nitrogen  for  the  improvement  of  this  type  of  soil;  and  it  also  shows  that 
nitrogen  need  not  be  purchased,  but  that  it  can  be  obtained  from  the  air  by 
growing  legume  crops  and  plowing  them  under  as  green  manure.  Of  course 
the  soil  can  be  very  markedly  improved  by  feeding  the  legume  crops  to  live 
stock  and  returning  the  resulting  farm  manure  to  the  land,  if  crops  of  legumes 
are  grown  frequently  enough  and  if  the  farm  manure  produced  is  sufficiently 
abundant  and  is  saved  and  applied  with  care. 

When  this  type  of  soil  is  to  be  prepared  for  seeding  down,  it  may  well  be 
treated  with  five  tons  per  acre  of  ground  limestone,  in  order  to  encourage  the 
growth  of  clover  and  thus  make  possible  the  accumulation  of  nitrogen,  the  element 
in  which  this  type  is  most  deficient  wherever  it  has  been  long  under  cultivation. 
As  a rule,  it  is  not  advisable  to  try  to  enrich  this  soil  in  phosphorus,  because 
of  the  fact  that  erosion,  which  is  sure  to  occur  to  some  extent,  will  renew  the 
supply  from  the  subsoil. 

Field  experiments  covering  nine  years  have  been  conducted  on  the  yellow 
silt  loam  at  Vienna,  Johnson  county.  Here  heavy  applications  of  ground  lime- 
stone paid  nearly  200  percent  on  the  investment,  and  about  half  the  limestone 
applied  still  remained  in  the  soil  for  the  benefit  of  later  crops.  Neither  phos- 
phorus nor  potassium  produced  sufficient  increase  to  pay  the  cost.  (The  details 
of  these  investigations  are  reported  in  Soil  Report  No.  3,  “Hardin  County 
Soils.”) 

One  of  the  most  profitable  crops  to  grow'  on  this  land  is  alfalfa.  To  get 
alfalfa  well  started  requires  a liberal  use  of  limestone,  thoro  inoculation  with 
nitrogen-fixing  bacteria,  and  a moderate  application  of  farm  manure.  If  ma- 
nure is  not  available,  it  is  well  to  apply  about  500  pounds  per  acre  of  acid  phos- 
phate or  steamed  bone  meal,  mix  it  with  the  soil,  by  disking  if  possible,  and  then 
plow  it  under.  The  limestone  (about  5 tons)  should  be  applied  after  plowing 
and  mixed  with  the  surface  soil  in  the  preparation  of  the  seed  bed.  The  special 
purpose  of  this  treatment  is  to  give  the  alfalfa  a quick  start  in  order  that  it 
may  grow  rapidly  and  thus  protect  the  soil  from  washing. 

Light  Gray  Silt  Loam  on  Tight  Clay  (332) 

Light  gray  silt  loam  on  tight  clay  occurs  in  old  timbered  regions  where 
the  land  is  so  nearly  level  that  there  is  no  chance  for  rapid  surface  drainage. 
It  is  the  most  common  level  timber  land  of  Bond  county  and  occupies  a total 
area  of  16.45  square  miles  (10,528  acres),  or  4.42  percent  of  the  county.  The 
type  has  two  distinct  phases:  one  phase  is  slightly  better  surface-drained,  but 
lighter  colored  and  less  productive;  the  other  is  more  swampy  (water  oaks  com- 
monly grow  on  this  phase),  with  a darker  surface  and  a greater  porosity,  so 
that  better  drainage  is  probably  possible.  The  amount  of  this  latter  phase  is 
small  as  compared  with  the  former  and  is  frequently  confined  to  narrow  strips 
too  small  to  map. 


191S ] 


Bond  County 


41 


“Scalds”  are  found  on  this  type,  but  they  are  not  so  common  as  on  the 
gray  silt  loam  on  tight  clay  (330)  or  the  brown-gray  silt  loam  on  tight 
clay  (328). 

The  surface  soil  of  this  type,  0 to  6%  inches,  is  a light  gray  to  almost 
white  silt  loam  containing  1.6  percent  of  organic  matter,  or  16  tons  per  acre. 
It  is  somewhat  porous  and  incoherent,  but  contains  sufficient  clay  to  bake  when 
puddled  and  dried.  When  the  moisture  content  is  at  its  optimum,  the  soil 
works  very  well,  but  because  of  the  low  organic-matter  content  it  “runs  to- 
gether” badly  with  rains  or  with  freezing  and  thawing  when  wet.  The  surface 
soil,  as  well  as  the  subsurface  and  subsoil,  contains  large  numbers  of  iron  oxid 
concretions  of  various  sizes  up  to  one-fourth  inch  in  diameter.  Small  pebbles 
of  quartz  are  sometimes  found,  possibly  having  been  brought  to  the  surface 
from  the  underlying  glacial  till  by  burrowing  animals  during  past  centuries. 

The  subsurface  varies  from  light  gray  silt  loam  to  a white  silt,  compact 
but  friable,  from  2 to  20  inches  in  thickness.  Water  passes  thru  it  slowly. 

The  subsoil  consists  of  a compact  yellowish  gray  clayey  silt,  or  silty  clay, 
only  slowly  pervious  to  water,  but  usually  not  quite  so  tight  as  the  correspond- 
ing layer  of  the  gray  silt  loam  on  tight  clay  (330).  In  places  the  type  has  a 
somewhat  more  friable  subsoil  which  is  not  so  nearly  impervious  as  the  sub- 
surface. Where  the  tight  clay  occurs  at  the  greater  depths  from  the  surface, 
it  is  less  objectionable. 

An  invoice  of  plant  food  shows  great  need  of  nitrogen  and  phosphorus. 
With  provision  made  for  these,  with  a liberal  use  of  limestone  and  organic 
matter,  including  legume  residues  or  farm  manure,  and  with  proper  surface 
drainage,  the  soil  can  be  made  highly  productive. 

White  Silt  Loam  on  Tight  Clay  (332.1) 

White  silt  loam  on  tight  clay  is  found  on  the  level  upland,  and  it  is  now  or 
was  formerly  covered  by  a growth  of  stunted  trees,  principally  the  so-called 
post  oak.  The  term  post-oak  flat  or  post-oak  soil  is  commonly  applied  to  this 
type,  altho  these  terms  are  often  used  locally  to  designate  the  poorer  phase  of 
light  gray  silt  loam  on  tight  clay  (332).  The  surface  drainage  is  very  poor 
and  the  subsoil  is  almost  impervious.  The  total  mapped  area  of  this  type  in 
the  county  is  only  435  acres,  but  there  are  many  small  areas  that  cannot  be 
shown  on  the  map.  Much  of  the  light-gray  silt  loam  on  tight  clay  (332)  grades 
toward  this  related  type  (332.1). 

Where  land  of  this  type  has  been  cultivated,  the  surface  soil,  0 to  6% 
inches,  is  a white  silt;  in  the  timbered  areas  this  characteristic  white  silt  is 
sometimes  overlain  by  an  inch  or  two  of  dark  gray  silt  loam.  The  organic- 
matter  content  of  this  layer  is  even  lower  in  this  type  than  in  the  light  gray  silt 
loam,  containing  only  1.25  percent,  or  12.5  tons  per  acre.  Because  of  this 
lack  of  organic  matter  and  the  high  silt  content,  the  soil  “runs  together”  badly. 
Iron  oxid  concretions  are  always  present. 

The  subsurface  layer  is  a white  silt  with  many  iron  oxid  concretions.  It 
varies  from  4 to  16  inches  in  thickness  and  passes  abruptly  into  the  subsoil. 

The  subsoil  is  a light  yellow,-  iron-stained,  silty  clay,  very  tough  and  plastic 
when  wet  and  hard  when  dry,  with  an  organic-matter  content  of  only  .30 
percent.  Both  subsurface  and  subsoil  are  almost  impervious. 


42 


Soil  Report  No.  8 


[ October , 


The  first  need  of  this  soil  is  ground  limestone,  the  initial  application  of 
which  may  well  be  4 to  6 tons  per  acre.  The  increase  in  organic  matter  should 
follow  as  rapidly  as  practicable.  Legumes,  such  as  cowpeas,  clover,  and  sweet 
clover,  should  be  grown  and  turned  under  with  farm  manure  and  crop  residues, 
such  as  straw  and  corn  stalks.  For  such  flat,  poorly  drained  land,  alsike  is 
usually  a more  satisfactory  crop  than  red  clover.  Finally,  phosphorus  should 
be  used  liberally  in  connection  with  the  organic  matter  in  order  to  provide  a 
permanent  system  of  soil  improvement. 

(c)  Ridge  Soils 
Yellow  Silt  Loam  (235) 

The  morainal  ridges  of  the  lower  Illinois  glaciation  have  given  a slight 
variation  to  the  usual  level  topography  of  this  region,  their  height  varying 
from  20  to  100  feet  or  more.  A fine  covering  of  loess  from  5 to  10  feet  deep, 
together  with  excellent  drainage,  has  resulted  in  the  formation  on  these  ridges 
of  a soil  known  as  yellow  silt  loam,  very  different  from  the  surrounding  prairie 
but  somewhat  resembling  in  texture  the  better  phase  of  the  yellow  silt  loam 
timber  land  (335)  already  described.  The  total  area  of  this  type  in  Bond 
county  is  12.41  square  miles  (7,942  acres)  or  3.33  percent  of  the  county. 

The  surface  soil,  0 to  6%  inches,  is  a yellow  or  yellowish  brown  silt  loam 
with  a considerable  amount  of  very  fine  sand.  The  color  varies  with  the  amount 
of  erosion  that  has  taken  place.  Where  little  washing  has  occurred,  the  color 
may  be  a yellowish  brown,  while  with  more  washing  it  becomes  yellow.  The 
soil  is  loose,  porous,  and  readily  pervious  to  water.  Its  physical  composition  is 
such  as  to  give  it  great  water-retaining  power  and  strong  capillarity,  so  that 
it  will  resist  drouth  well  if  properly  cultivated.  The  organic-matter  content 
is  about  1.8  percent,  or  18  tons  per  acre. 

The  subsurface  layer,  extending  from  6%  to  about  20  inches  below  the 
surface,  varies  from  a yellowish  brown  silt  loam  to  a yellow  silt  or  a slightly 
clayey  silt.  It  becomes  more  compact  with  depth  but  still  retains  its  pervious- 
ness and  capillary  power. 

The  upper  part  of  the  subsoil  is  somewhat  compact  and  slightly  clayey,  but 
it  passes  into  a friable  silt  containing  some  fine  sand.  It  is  yellow  or  reddish 
yellow  in  color.  Below  24  inches  it  is  sometimes  slightly  gray  or  marked  with 
gray  blotches,  and  when  grading  toward  yellow-gray  silt  loam  (334)  it  becomes 
decidedly  gray  in  places.  This  soil,  considered  from  a physical  standpoint,  is 
almost  as  good  as  could  be  desired.  In  respect  to  aeration,  drainage,  and  ability 
to  withstand  drouth,  it  is  one  of  the  best  upland  types  in  the  county. 

The  organic-matter  content  should  be  increased  by  growing  clovers  and 
cowpeas,  and  these  should  be  turned  under  directly  or  as  farm  manure,  together 
with  crop  residues,  straw,  and  corn  stalks.  The  maintenance  of  organic  matter 
is  made  more  difficult  because  of  the  rolling  character  of  the  land,  which  facili- 
tates erosion  and  the  removal  of  the  best  soil. 

This  ridge  soil  contains  no  limestone.  As  a rule  the  subsoil  is  markedly 
acid,  but  with  a liberal  use  of  limestone  and  thoro  inoculation  it  becomes  a 
very  good  soil  for  alfalfa,  altho  where  badly  worn  manure  may  well  be  used 
in  getting  the  alfalfa  started.  (See  also  discussion  of  yellow  silt  loam,  No.  335.) 


1913] 


Bond  Coonty 


43 


Gray -Red  Silt  Loam  on  Tight  Clay  (233) 

Gray-red  silt  loam  on  tight  clay  occurs  on  some  of  the  ridges,  which  are 
in  part  at  least  of  preglacial  origin,  rising  from  5 to  75  feet  above  the  sur- 
rounding upland.  As  a rule,  it  is  one  of  the  poorest  upland  types  in  the  state, 
but  most  of  the  areas  in  this  county  are  a better  phase  of  the  type  than  ordinary. 
This  type  in  Bond  county  occupies  922  acres.  In  some  places  it  may  suffer 
from  erosion,  but  it  is  extremely  doubtful  whether  tile-drainage  would  profitably 
benefit  this  soil, — at  best,  not  until  other  methods  of  improvement  have  been 
put  into  practice. 

The  surface  soil  is  a friable  gray  silt  loam  very  similar  to  that  of  the  gray 
silt  loam  on  tight  clay  (330). 

The  subsurface  layer  also  resembles  the  corresponding  stratum  in  gray 
silt  loam  on  tight  clay  both  in  texture  and  thickness,  but  it  contains  more  of 
the  higher  oxid  of  iron,  which  gives  it  a reddish  color.  As  a rule,  the  organic- 
matter  content  is  low. 

The  subsoil  lies  from  7 to  20  inches  below  the  surface  and  consists  of  a 
layer  of  very  plastic,  gummy,  almost  impervious  red  clay,  varying  from  4 to 
12  inches  in  thickness  and  underlain  by  a less  plastic  and  more  silty  stratum. 
When  dry,  the  red  clay  becomes  so  hard  that  it  is  next  to  impossible  to  bore 
into  it  with  an  auger.  Where  this  layer  appears  at  the  surface,  as  it  does  on 
some  small  eroded  areas,  the  land  is  practically  worthless. 

This  type  of  soil  closely  resembles  the  more  extensive  gray  silt  loam  on  tight 
clay  (330).  Methods  for  its  improvement  are  the  same,  except  on  areas  sub- 
ject to  considerable  erosion,  where  the  addition  of  phosphorus  is  not  advised. 
This  factor  of  erosion,  together  with  the  tighter  texture,  as  a rule  will  make 
the  improvement  of  this  type  less  satisfactory  than  that  of  the  gray  silt  loam. 

Yellow  Fine  Sandy  Silt  Loam  (245) 

Yellow  fine  sandy  silt  loam  occupies  some  of  the  highest  glacial  ridges, 
which  have  been  covered  with  a deposit  of  loess  varying  from  10  to  20  feet  in 
thickness  and  of  slightly  coarser  grade  than  the  surrounding  deposits.  The 
type  has  always  been  well  drained  and  as  a result  is  well  oxidized.  Practically 
all  of  it  was  originally  forested.  The  total  area  in  Bond  county  is  almost  2 
square  miles  (1,267  acres),  or  .53  percent  of  the  county. 

The  surface  soil,  0 to  6%  inches,  is  a brownish  yellow  to  a yellowish  brown 
silt  loam  containing  from  25  to  35  percent  of  fine  sand.  It  also  contains  much 
coarse  silt.  This  mixture  furnishes  the  basis  for  an  ideal  soil.  It  is  easy  to 
work,  porous,  and  at  the  same  time  has  great  water-retaining  power  and  strong 
capillarity,  so  that  it  will  resist  drouth  well  when  properly  cared  for.  The 
organic-matter  content  is  about  2 percent,  or  20  tons  per  acre. 

The  subsurface  layer  varies  from  a yellowish  brown  to  a yellow  silt  loam, 
containing  slightly  more  clay  than  the  surface  soil.  It  becomes  somewhat 
more  compact  with  depth,  but  still  retains  its  perviousness  and  capillary  power. 

The  upper  part  of  the  subsoil  is  a somewhat  compact,  clayey  silt,  but  it 
passes  into  a very  pervious  friable  silt  containing  considerable  amounts  of  fine 
sand  and  coarse  silt.  It  is  yellow  or  reddish  yellow  in  color  and  rarely  con- 
tains the  gray  blotches  which  are  so  common  in  yellow  silt  loam  (235). 


44 


Soil  Report  No.  8 


[October, 


From  a physical  standpoint  this  type  is  the  best  upland  soil  in  the  county. 
As  a rule  it  is  low  in  organic  matter  and  slightly  acid.  The  organic  matter 
should  of  course  be  increased,  altho  the  rolling  character  of  the  type  renders 
this  problem  difficult. 

Like  most  soils  that  are  subject  to  much  erosion,  this  type  is  poor  in  nitro- 
gen and  rich  in  potassium.  The  supply  of  phosphorus  is  low  but  it  increases 
with  depth,  so  that  erosion  enriches  the  soil  in  that  constituent.  For  this  rea- 
son and  also  because  of  the  extensive  feeding  range  afforded  by  the  porous 
character  of  the  soil,  the  addition  of  phosphorus  is  not  advised. 

Very  marked  and  profitable  improvement  can  be  made  with  the  use  of 
limestone  and  legumes,  and  these  means  are  sufficient  to  provide  for  permanent 
systems  of  moderately  high  production. 

(d)  Bottom-Land  Soils 
Deep  Gray  Silt  Loam  (1331) 

Deep  gray  silt  loam  occurs  along  most  of  the  streams  of  the  lower  Illinois 
glaciation.  It  is  formed  from  the  gray,  yellow-gray,  and  yellow  silt  loams  that 
have  washed  down  from  the  upland  and  blended  into  a gray  or  yellowish  gray 
soil.  During  floods  these  lands  in  most  places  still  receive  frequent  or  oc- 
casional deposits  of  new  material.  Aside  from  the  difficulties  from  overflow 
and  lack  of  drainage,  this  is  the  most  valuable  extensive  soil  type  in  Bond 
county.  • 

This  type  occupies  a total  area  of  26.22  square  miles  (16,781  acres),  or 
7.05  percent  of  the  county.  It  lies  so  low  that  the  drainage  is  generally  poor, 
and  there  is  often  much  difficulty  in  getting  sufficient  outlet  for  under-drainage 
or  sometimes  even  for  adequate  surface  drainage.  Where  a satisfactory  outlet 
can  be  secured,  tile  drainage  greatly  benefits  this  soil. 

The  surface  soil  is  a gray  silt  loam,  varying  from  a gray  to  a drab  in  color 
and  from  a loam  to  a clayey  silt  loam  in  physical  composition. 

The  subsurface  and  subsoil  are  about  the  same  as  the  surface  except  that 
they  are  lighter  in  color  and  commonly  a little  more  clayey  with  depth.  In  the 
smaller  stream  bottoms,  the  recent  deposits  are  frequently  yellow  and  slightly 
sandy,  and  consequently  there  is  found  in  places  a stratum  of  yellow  on  the 
gray,  varying  from  a few  inches  to  a foot  or  more  in  thickness. 

In  phosphorus  content,  this  type  exceeds  the  most  common  prairie  soil  of 
the  corn  belt.  The  porous  subsoil  affords  such  a deep  feeding  range  that  the 
application  of  that  element  is  not  likely  to  give  profitable  returns,  except  where 
overflow  is  not  common  and  where  the  soil  has  been  long  cropped. 

The  soil  of  this  type  is  acid.  It  is  also  rather  poor  in  nitrogen,  altho  this 
deficiency  is  counterbalanced  to  a large  extent  by  the  great  depth  and  porosity 
of  the  soil. 

While  the  overflow  and  drainage  problems  are  of  first  importance,  where 
these  are  under  sufficient  control  to  permit  of  soil  improvement  the  use  of  lime- 
stone and  the  addition  of  nitrogenous  organic  matter,  such  as  clover  or  manure 
plowed  under,  will  make  this  soil  still  more  productive ; and  if  the  land  is  pro- 
tected from  the  usual  overflow  deposits,  the  addition  of  phosphorus  will  ulti- 
mately be  necessary;  even  now  it  is  likely  to  be  profitable  for  the  highest  im- 


19JS] 


Bond  County 


45 


provement  of  the  soil.  To  illustrate,  it  may  be  pointed  out  that  on  the  Uni- 
versity Farm  at  Urbana,  land  that  has  yielded  72.5  bushels  of  corn  per  acre  as 
a six-year  average,  in  a rotation  of  corn,  oats,  and  clover,  with  limestone  and 
organic  manures  provided,  has  with  the  addition  of  phosphorus  made  an  aver- 
age of  88.5  bushels  during  the  same  years.  Thus  there  may  be  room  for  phos- 
phorus “at  the  top,”  even  where  very  satisfactory  yields  may  be  secured  with- 
out its  application  and  where  other  factors  are  of  first  importance. 

Deep  Brown  Silt  Loam  (1326) 

The  basic  material  for  the  deep-brown  silt  loam  naturally  belongs  to  the 
middle  Illinois  glaciation  with  its  dark-colored  upland  soils,  but  this  has  been 
covered  by  loads  of  dark  sediment  brought  down  by  Shoal  creek  and  its  tribu- 
taries and  deposited  over  their  flood  plains.  This  sediment  has  been  more  or 
less  mixed  with  material  brought  in  by  small  streams  from  the  light-colored 
upland  soils,  resulting  in  the  formation  of  soils  intermediate  in  character  or 
lacking  in  uniformity.  The  bottoms  along  the  streams  vary  in  width  from  a 
few  rods  to  more  than  a mile.  ' The  soil  of  the  narrower  bottoms  has  a tendency 
to  be  darker  than  that  of  the  wider  areas.  This  type  occupies  13.74  square 
miles  (8,794  acres),  or  3.7  percent  of  the  area  of  Bond  county.  In  topography 
it  is  flat  or  with  very  slight  undulations  that  represent  old  stream  or  overflow 
channels.  Better  drainage  is  needed  in  much  of  this  area. 

The  surface  soil,  0 to  6%  inches,  is  a brown  silt  loam,  varying  in  places, 
especially  in  the  flat,  poorly  drained  areas,  to  a gray  silt  loam.  While  the 
organic-matter  content  of  this  type  is  not  high,  yet  it  is  more  easily  maintained 
here  than  in  the  upland  because  of  the  occasional  overflow  and  the  consequent 
deposition  of  material  rich  in  organic  matter.  The  physical  composition  of  this 
soil  varies  from  a heavy  silt  loam  to  a sandy  loam,  but  the  areas  of  these  extreme 
types,  especially  the  latter,  are  so  small  and  so  changeable  that  it  would  not 
mean  much  to  show  them  on  the  map,  as  the  next  flood  might  change  their 
boundaries. 

The  subsurface  varies  from  a brown  silt  loam-to  a gray  silt  loam. 

The  subsoil  varies  in  color  from  a brown  to  a yellowish  drab,  and  in  physical 
composition  from  a clayey  silt  to  a sandy  loam  or  sometimes  even  a sand  in  the 
lower  subsoil. 

Under  the  usual  conditions  it  is  very  doubtful  whether  any  materials  can 
be  applied  to  this  soil  with  profit,  but  where  feasible  some  legumes  should  be 
grown  in  the  crop  rotation. 


46 


Soil  Report  No.  8 


[October, 


APPENDIX 

A study  of  the  soil  map  and  the  tabular  statements  concerning  crop  require- 
ments, the  plant-food  content  of  the  different  soil  types,  and  the  actual  results 
secured  from  definite  field  trials  with  different  methods  or  systems  of  soil  im- 
provement, and  a careful  study  of  the  discussion  of  general  principles  and  of 
the  descriptions  of  individual  soil  types,  will  furnish  the  most  necessary  and  use- 
ful information  for  the  practical  improvement  and  permanent  preservation  of 
the  productive  power  of  every  kind  of  soil  on  every  farm  in  the  county. 

More  complete  information  concerning  the  most  extensive  and  important  soil 
types  in  the  great  soil  areas  in  all  parts  of  Illinois  is  contained  in  Bulletin  123, 
“The  Fertility  in  Illinois  Soils,”  which  contains  a colored  general  soil-survey 
map  of  the  entire  state. 

Other  publications  of  general  interest  are : 

Bulletin  No.  76,  “Alfalfa  on  Illinois  Soils’’ 

Bulletin  No.  94,  “Nitrogen  Bacteria  and  Legumes” 

Bulletin  No.  115,  “Soil  Improvement  for  the  Worn  Hill  Lands  of  Illinois” 

Bulletin  No.  125,  “Thirty  Years  of  Crop  Rotation  on  the  Common  Prairie  Lands  of 
Illinois  ’ ’ 

Circular  No.  82,  “Physical  Improvement  of  Soils” 

Circular  No.  110,  “Ground  Limestone  for  Acid  Soils” 

Circular  No.  127,  “Shall  We  Use  Natural  Rock  Phosphate  or  Manufactured  Acid  Phos- 
phate for  the  Permanent  Improvement  of  Illinois  Soils?” 

Circular  No.  129,  “The  Use  of  Commercial  Fertilizers” 

Circular  No.  149,  ‘ ‘ Results  of  Scientific  Soil  Treatment  ’ ’ and  ‘ ‘ Methods  and  Results  of 
Ten  Years’  Soil  Investigation  in  Illinois” 

Circular  No.  165,  “Shall  We  Use  ‘Complete’  Commercial  Fertilizers  in  the  Corn  Belt?” 
Circular  No.  167,  “The  Illinois  System  of  Permanent  Fertility” 

Note. — Information  as  to  where  to  obtain  limestone,  phosphate,  bone  meal,  and  potas- 
sium salts,  methods  of  application,  etc.,  will  also  be  found  in  Circulars  110  and  165. 

Soil  Survey  Methods 

The  detail  soil  survey  of  a county  consists  essentially  of  ascertaining,  and 
indicating  on  a map,  the  location  and  extent  of  the  different  soil  types;  and, 
since  the  value  of  the  survey  depends  upon  its  accuracy,  every  reasonable  means 
is  employed  to  make  it  trustworthy.  To  accomplish  this  object  three  things  are 
essential:  first,  careful,  well-trained  men  to  do  the  work;  second,  an  accurate 
base  map  upon  which  to  show  the  results  of  the  work;  and,  third,  the  means 
necessary  to  enable  the  men  to  place  the  soil-type  boundaries,  streams,  etc., 
accurately  upon  the  map. 

The  men  selected  for  the' work  must  be  able  to  keep  their  location  exactly 
and  to  recognize  the  different  soil  types,  with  their  principal  variations  and  lim- 
its, and  they  must  show  these  upon  the  maps  correctly.  A definite  system  is 
employed  in  checking  up  this  work.  As  an  illustration,  one  soil  expert  will  sur- 
vey and  map  a strip  80  rods  or  160  rods  wide  and  any  convenient  length,  while 
his  associate  will  work  independently  on  another  strip  adjoining  this  area,  and, 
if  the  work  is  correctly  done,  the  soil  type  boundaries  must  match  up  on  the 
line  between  the  two  strips. 

An  accurate  base  map  for  field  use  is  absolutely  necessary  for  soil  mapping. 
The  base  maps  are  made  on  a scale  of  one  inch  to  the  mile.  The  official  data 
of  the  original  or  subsequent  land  survey  are  used  as  a basis  in  the  construc- 
tion of  these  maps,  while  the  most  trustworthy  county  map  available  is  used  in 


1918 ] 


Bond  County 


47 


locating  temporarily  the  streams,  roads,  and  railroads.  Since  the  best  of  these 
published  maps  have  some  inaccuracies,  the  location  of  every  road,  stream,  and 
railroad  must  be  verified  by  the  soil  surveyors,  and  corrected  if  wrongly  located. 
In  order  to  make  these  verifications  and  corrections,  each  survey  party  is  pro- 
vided with  an  odometer  for  measuring  distances,  and  a plane  table  for  deter- 
mining directions  of  angling  roads,  railroads,  etc. 

Each  surveyor  is  provided  with  a base  map  of  the  proper  scale,  which  is 
carried  with  him  in  the  field ; and  the  soil-type  boundaries,  ditches,  streams,  and 
necessary  corrections  are  placed  in  their  proper  locations  upon  the  map  while 
the  mapper  is  on  the  area.  Each  section,  or  square  mile,  is  divided  into  40-acre 
plots  on  the  map,  and  the  surveyor  must  inspect  every  ten  acres  and  determine 
the  type  or  types  of  soil  composing  it.  The  different  types  are  indicated  on  the 
map  by  different  colors,  pencils  for  this  purpose  being  carried  in  the  field. 

A small  auger  40  inches  long  foi^ns  for  each  man  an  invaluable  tool  with 
which  he  can  quickly  secure  samples  of  the  different  strata  for  inspection.  An 
extension  for  making  the  auger  80  inches  long  is  carried  by  each  party,  so  that 
any  peculiarity  of  the  deeper  subsoil  layers  may  be  studied.  Each  man  carries 
a compass  to  aid  in  keeping  directions.  Distances  along  roads  are  measured  by 
an  odometer  attached  to  the  axle  of  the  vehicle,  while  distances  in  the  field  off 
the  roads  are  determined  by  pacing,  an  art  in  which  the  men  become  expert  by 
practice.  The  soil  boundaries  can  thus  be  located  with  as  high  a degree  of  ac- 
curacy as  can  be  indicated  by  pencil  on  the  scale  of  one  inch  to  the  mile. 


Soil  Characteristics 


The  unit  in  the  soil  survey  is  the  soil  type,  and  each  type  possesses  more  or 
less  definite  characteristics.  The  line  of  separation  between  adjoining  types  is 
usually  distinct,  but  sometimes  one  type  grades  into  another  so  gradually  that 
it  is  very  difficult  to  draw  the  line  between  them.  In  such  exceptional  cases, 
some  slight  variation  in  the  location  of  soil-type  boundaries  is  unavoidable. 

Several  factors  must  be  taken  into  account  in  establishing  soil  types.  These 
are  (1)  the  geological  origin  of  the  soil,  whether  residual,  glacial,  loessial,  al- 
luvial, colluvial,  or  cumulose;  (2)  the  topography,  or  lay  of  the  land;  (3)  the 
native  vegetation,  as  forest  or  prairie  grasses;  (4)  the  structure,  or  the  depth 
and  character  of  the  surface,  subsurface,  and  subsoil ; ( 5 ) the  physical,  or  me- 
chanical, composition  of  the  different  strata  composing  the  soil,  as  the  percent- 
ages of  gravel,  sand,  silt,  clay,  and  organic  matter  which  they  contain;  (6)  the 
texture,  or  porosity,  granulation,  friability,  plasticity,  etc.;  (7)  the  color  of  the 
strata;  (8)  the  natural  drainage;  (9)  the  agricultural  value,  based  upon  its 
natural  productiveness;  (10)  the  ultimate  chemical  composition  and  reaction. 

The  common  soil  constituents  are  indicated  in  the  following  outline : 


Soil 

constituents 


Organic 
| matter 

- 

Inorganic 

matter 


("Comprising  undecomposed  and  partially  decayed 
| vegetable  or  organic  material 


Clay 001  mm.1  and  less 

Silt 001  mm.  to  .03  mm. 

Sands 03  mm.  to  1.  mm. 

Gravel 1.  tnm.  to  32  mm. 

Stones 32.  mm.  and  over 


Further  discussion  of  these  constituents  is  given  in  Circular  82. 


*25  millimeters  equal  1 inch. 


48 


Soil  Report  No.  8 


[October, 


Groups  of  Soil  Types 

The  following  gives  the  different  general  groups  of  soils: 

Peats — Consisting  of  35  percent  or  more  of  organic  matter,  sometimes  mixed 
with  more  or  less  sand  or  silt. 

Peaty  loams — 15  to  35  percent  of  organic  matter  mixed  with  much  sand. 
Some  silt  and  a little  clay  may  be  present. 

Mucks — 15  to  35  percent  of  partly  decomposed  organic  matter  mixed  with 
much  clay  and  silt. 

Clays — Soils  with  more  than  25  percent  of  clay,  usually  mixed  with  much 

silt. 

Clay  loams — Soils  with  from  15  to  25  percent  of  clay,  usually  mixed  with 
much  silt  and  some  sand. 

Silt  loams— Soils  with  more  than  50  percent  of  silt  and  less  than  15  percent 
of  clay,  mixed  with  some  sand. 

Loams — Soils  with  from  30  to  50  percent  of  sand  mixed  with  much  silt  and 
a little  clay. 

Sandy  loams — Soils  with  from  50  to  75  percent  of  sand. 

Fine  sandy  loams — Soils  with  from  50  to  75  percent  of  fine  sand  mixed  with 
much  silt  and  little  clay. 

Sands — Soils  with  more  than  75  percent  of  sand. 

Gravelly  loams — Soils  with  25  to  50  percent  of  gravel  with  much  sand  and 
some  silt. 

Gravels — Soils  with  more  than  50  percent  of  gravel  and  much  sand. 

Stony  loams — Soils  containing  a considerable  number  of  stones  over  one  inch 
in  diameter. 

Bock  outcrop— Usually  ledges  of  rock  having  no  direct  agricultural  value. 

More  or  less  organic  matter  is  found  in  all  the  above  groups. 

Supply  and  Liberation  of  Plant  Food 

The  productive  capacity  of  land  in  humid  sections  depends  almost  wholly 
upon  the  power  of  the  soil  to  feed  the  crop ; and  this,  in  turn,  depends  both 
upon  the  stock  of  plant  food  contained  in  the  soil  and  upon  the  rate  at  which 
it  is  liberated,  or  rendered  soluble  and  available  for  use  in  plant  growth. 
Protection  from  weeds,  insects,  and  fungous  diseases,  tho  exceedingly  important, 
is  not  a positive  but  a negative  factor  in  crop  production. 

The  chemical  analysis  of  the  soil  gives  the  invoice  of  fertility  actually  pres- 
ent in  the  soil  strata  sampled  and  analyzed,  but  the  rate  of  liberation  is  gov- 
erned by  many  factors,  some  of  which  may  be  controlled  by  the  farmer,  while 
others  are  largely  beyond  his  control.  Chief  among  the  important  controllable 
factors  which  influence  the  liberation  of  plant  food  are  limestone  and  decaying 
organic  matter,  which  may  be  added  to  the  soil  by  direct  application  of  ground 
limestone  and  farm  manure.  Organic  matter  may  be  supplied  also  by  green- 
manure  crops  and  crop  residues,  such  as  clover,  cowpeas,  straw,  and  corn  stalks. 
The  rate  of  decay  of  organic  matter  depends  largely  upon  its  age  and  origin, 


191S ] 


Bond  County 


49 


and  it  may  be  hastened  by  tillage.  The  chemical  analysis  shows  correctly  the 
total  organic  carbon,  which  represents,  as  a rule,  but  little  more  than  half  the 
organic  matter;  so  that  20,000  pounds  of  organic  carbon  in  the  plowed  soil  of 
an  acre  correspond  to  nearly  20  tons  of  organic  matter.  But  this  organic  mat- 
ter consists  largely  of  the  old  organic  residues  that  have  accumulated  during  the 
past  centuries  because  they  were  resistant  to  decay,  and  2 tons  of  clover  or 
ccwpeas  plowed  under  may  have  greater  power  to  liberate  plant  food  than  the 
20  tons  of  old,  inactive  organic  matter.  The  recent  history  of  the  individual 
farm  or  field  must  be  depended  upon  for  information  concerning  recent  addi 
tions  of  active  organic  matter,  whether  in  applications  of  farm  manure,  in 
legume  crops,  or  in  grass-root  sods  of  old  pastures. 

Probably  no  agricultural  fact  is  more  generally  known  by  farmers  and  land- 
owners  than  that  soils  differ  in  productive  power.  Even  tho  plowed  alike  and 
at  the  same  time,  prepared  the  same  way,  planted  the  same  day  with  the  same 
kind  of  seed,  and  cultivated  alike,  watered  by  the  same  rains  and  warmed  by 
the  same  sun,  nevertheless  the  best  acre  may  produce  twice  as  large  a crop  as 
the  poorest  acre  on  the  same  farm,  if  not,  indeed,  in  the  same  field ; and  the 
fact  should  be  repeated  and  emphasized  that  with  the  normal  rainfall  of  Illi- 
nois the  productive  power  of  the  land  depends  primarily  upon  the  stock  of  plant 
food  contained  in  the  soil  and  upon  the  rate  at  which  it  is  liberated,  just  as 
the  success  of  the  merchant  depends  primarily  upon  his  stock  of  goods  and  the 
rapidity  of  sales.  In  both  cases  the  stock  of  any  commodity  must  be  increased 
or  renewed  whenever  the  supply  of  such  commodity  becomes  so  depleted  as  to 
limit  the  success  of  the  business,  whether  on  the  farm  or  in  the  store. 

As  the  organic  matter  decays,  certain  decomposition  products  are  formed, 
including  much  carbonic  acid,  some  nitric  acid,  and  various  organic  acids,  and 
these  have  power  to  act  upon  the  soil  and  dissolve  the  essential  mineral  plant 
foods,  thus  furnishing  soluble  phosphates,  nitrates,  and  other  salts  of  potassium, 
magnesium,  calcium,  etc.,  for  the  use  of  the  growing  crop. 

As  already  explained,  fresh  organic  matter  decomposes  much  more  rapidly 
than  old  humus,  which  represents  the  organic  residues  most  resistant  to  decay 
and  which  consequently  has  accumulated  in  the  soil  during  the  past  centuries. 
The  decay  of  this  old  humus  can  be  hastened  both  by  tillage,  which  maintains 
a porus  condition  and  thus  permits  the  oxygen  of  the  air  to  enter  the  soil  more 
freely  and  to  effect  the  more  rapid  oxidation  of  the  organic  matter,  and  also  by 
incorporating  with  the  old,  resistant  residues  some  fresh  organic  matter,  such 
as  farm  manure,  clover  roots,  etc.,  which  decay  rapidly  and  thus  furnish  or  lib- 
erate organic  matter  and  inorganic  food  for  bacteria,  the  bacteria,  under  such 
favorable  conditions,  appearing  to  have  power  to  attack  and  decompose  the  old 
humus.  It  is  probably  for  this  reason  that  peat,  a very  inactive  and  inefficient 
fertilizer  when  used  by  itself,  becomes  much  more  effective  when  composted  with, 
fresh  farm  manure ; so  that  two  tons  of  the  compost1  may  be  worth  as  much  as 
two  tons  of  manure,  but  if  applied  separately,  the  peat  has  little  value.  Bac- 
terial action  is  also  promoted  by  the  presence  of  limestone. 

'In  his  book,  “Fertilizers,”  published  in  1839,  Cuthhert  W.  Johnson  reported  such  com- 
post to  have  been  much  used  in  England  and  to  be  valued  as  highly,  “weight  for  weight,  as 
farm-yard  dung.” 


so 


Soil  Keport  No.  8 


f October, 


The  condition  of  the  organic  matter  of  the  soil  is  indicated  more  or  less 
definitely  by  the  ratio  of  carbon  to  nitrogen.  As  an  average,  the  fresh  organic 
matter  incorporated  with  soils  contains  about  twenty  times  as  much  carbon  as 
nitrogen,  but  the  carbohydrates  ferment  and  decompose  much  more  rapidly  than 
the  nitrogenous  matter ; and  the  old  resistant  organic  residues,  such  as  are  found 
in  normal  subsoils,  commonly  contain  only  five  or  six  times  as  much  carbon  as 
nitrogen.  Soils  of  normal  physical  composition,  such  as  loam,  clay  loam,  silt 
loam,  and  fine  sandy  loam,  when  in  good  productive  condition,  contain  about 
twelve  to  fourteen  times  as  much  carbon  as  nitrogen  in  the  surface  soil ; while 
in  old,  worn  soils  that  are  greatly  in  need  of  fresh,  active,  organic  manures,  the 
ratio  is  narrower,  sometimes  falling  below  ten  of  carbon  to  one  of  nitrogen. 
Soils  of  cut-over  or  burnt-over  timber  lands  sometimes  contain  so  much  partially 
decayed  wood  or  charcoal  as  to  destroy  the  value  of  the.  nitrogen-carbon  ratio 
for  the  purpose  indicated.  (Except  in  newly  made  alluvial  soils,  the  ratio  is 
usually  narrower  in  the  subsurface  and  subsoil  than  in  the  surface  stratum.) 

It  should  be  kept  in  mind  that  crops  are  not  made  out  of  nothing.  They 
are  composed  of  ten  different  elements  of  plant  food,  every  one  of  which  is 
absolutely  essential  for  the  growth  and  formation  of  every  agricultural  plant. 
Of  these  ten  elements  of  plant  food,  only  two  (carbon  and  oxygen)  are  secured 
from  the  air  by  all  agricultural  plants,  only  one  (hydrogen)  from  water,  and 
seven  from  the  soil.  Nitrogen,  one  of  these  seven  elements  secured  from  the 
soil  by  all  plants,  may  also  be  secured  from  the  air  by  one  class  of  plants 
(legumes),  in  case  the  amount  liberated  from  the  soil  is  insufficient;  but  even 
these  plants  (which  include  only  the  clovers,  peas,  beans,  and  vetches,  among 
our  common  agricultural  plants)  secure  from  the  soil  alone  six  elements  (phos- 
phorus, potassium,  magnesium,  calcium,  iron,  and  sulfur),  and  also  utilize  the 
soil  nitrogen  so  far  as  it  becomes  soluble  and  available  during  their  period  of 
growth. 

Plants  are  made  of  plant-food  elements  in  just  the  same  sense  that  a build- 
ing is  made  of  wood  and  iron,  brick,  stone,  and  mortar.  Without  materials, 
nothing  material  can  be  made.  The  normal  temperature,  sunshine,  rainfall,  and 
length  of  season  in  central  Illinois  are  sufficient  to  produce  50  bushels  of  wheat 
per  acre,  100  bushels  of  corn,  100  bushels  of  oats,  and  4 tons  of  clover  hay ; and, 
where  the  land  is  properly  drained  and  properly  tilled,  such  crops  would  fre- 
quently be  secured  if  the  plant  foods  were  present  in  sufficient  amounts  and 
liberated  at  a sufficiently  rapid  rate  to  meet  the  absolute  needs  of  the  crops. 

Crop  Requirements 

The  accompanying  table  shows  the  requirements  of  wheat,  corn,  oats,  and 
clover  for  the  five  most  important  plant-food  elements  which  the  soil  must  fur- 
nish. (Iron  and  sulfur  are  supplied  normally  in  sufficient  abundance  compared 
with  the  amounts  needed"  by  plants,  so  that  they  are  never  known  to  limit  the 
yield  of  general  farm  crops  grown  under  normal  conditions.) 


1913] 


Bond  County 


51 


Table  A. — Plant  Food  in  Wheat,  Corn,  Oats,  and  Clover 


Produce 

Nitro- 

Phos- 

Potas- 

Magne- 

Cal- 

Kind 

Amount 

gen 

phorus 

sium 

sium 

cium 

lbs. 

lbs. 

lbs. 

lbs. 

lbs. 

Wheat,  grain 

50  bu. 

71 

12 

13 

4 

1 

Wheat  straw.  

2%  tons 

25 

4 

45 

4 

10 

Corn,  grain 

100  bu. 

100 

17 

19 

7 

1 

Corn  stover 

3 tons 

48 

6 

52 

10 

21 

Corn  cobs 

% ton 

2 

2 

Oats,  grain 

100  bu. 

66 

11 

16 

4 

2 

Oat  straw 

2%  tons 

31 

5 

52 

7 

15 

Clover  seed 

4 bu. 

7 

2 

3 

1 

1 

Clover  hay 

4 tons 

160 

20 

120 

31 

117 

Total  in  grain  and  seed 

2441 

42 

51 

16 

4 

Total  in  four  crops.. 

5101 

77 

322 

68 

168 

IThese  amounts  include  the  nitrogen  contained  in  the  clover  seed  or  hay,  which,  how- 
ever, may  be  secured  from  the  air. 


To  be  sure,  these  are  large  yields,  but  shall  we  try  to  make  possible  the 
production  of  yields  only  half  or  a quarter  as  large  as  these,  or  shall  we  set  as 
our  ideal  this  higher  mark,  and  then  approach  it  as  nearly  as  possible  with 
profit  ? Among  the  four  .crops,  corn  is  the  largest,  with  a total  yield  of  more 
than  six  tons  per  acre;  and  yet  the  100-bushel  crop  of  corn  is  often  produced 
on  rich  pieces  of  land  in  good  seasons.  In  very  practical  and  profitable  systems 
of  farming,  the  Illinois  Experiment  Station  has  produced,  as  an  average  of  the 
six  years  1905  to  1910,  a yield  of  87  bushels  of  corn  per  acre  in  grain  farming 
(with  limestone  and  phosphorus  applied,  and  with  crop  residues  and  legume 
crops  turned  under),  and  90  bushels  per  acre  in  live-stock  farming  (with  lime- 
stone, phosphorus,  and  manure). 

The  importance  of  maintaining  a rich  surface  soil  cannot  be  too  strongly 
emphasized.  This  is  well  illustrated  by  data  from  the  Rothamsted  Experiment 
Station,  the  oldest  in  the  world.  On  Broadbalk  field,  where  wheat  has  been 
grown  since  1844,  the  average  yields  for  the  ten  years  1892  to  1901  were  12.3 
bushels  per  acre  on  Plot  3 (unfertilized)  and  31.8  bushels  on  Plot  7 (well  ferti- 
lized), but  the  amounts  of  both  nitrogen  and  phosphorus  in  the  subsoil  (9  to  27 
inches)  were  distinctly  greater  in  Plot  3 than  in  Plot  7,  thus  showing  that  the 
higher  yields  from  Plot  7 were  due  to  the  fact  that  the  plowed  soil  had  been 
enriched.  In  1893  Plot  7 contained  per  acre  in  the  surface  soil  (0  to  9 inches) 
about  600  pounds  more  nitrogen  and  900  pounds  more  phosphorus  than  Plot  3. 
Even  a rich  subsoil  has  little  value  if  it  lies  beneath  a worn-out  surface. 

Methods  op  Liberating  Plant  Food 

Limestone  and  decaying  organic  matter  are  the  principal  materials  which 
the  farmer  can  utilize  most  profitably  to  bring  about  the  liberation  of  plant 
food.  The  limestone  corrects  the  acidity  of  the  soil  and  thus  encourages  the 
development  not  only  of  the  nitrogen-gathering  bacteria  which  live  in  the  nodules 
on  the  roots  of  clover,  eowpeas,  and  other  legumes,  but  also  the  nitrifying 
bacteria,  which  have  power  to  transform  the  insoluble  and  unavailable  organic 


52 


Soil  Report  No.  8 


[October, 


nitrogen  into  soluble  and  available  nitrate  nitrogen.  At  the  same  time,  the 
products  of  this  decomposition  have  power  to  dissolve  the  minerals  contained 
in  the  soil,  such  as  potassium  and  magnesium,  and  also  to  dissolve  the  insoluble 
phosphate  and  limestone  which  may  be  applied  in  low-priced  forms. 

Tillage,  or  cultivation,  also  hastens  the  liberation  of  plant  food  by  permit- 
ting the  air  to  enter  the  soil  and  burn  out  the  organic  matter;  but  it  should 
never  be  forgotten  that  tillage  is  wholly  destructive,  that  it  adds  nothing  what- 
ever to  the  soil,  but  always  leaves  it  poorer.  Tillage  should  be  practiced  so 
far  as  is  necessary  to  prepare  a suitable  seed-bed  for  root  development  and 
also  for  the  purpose  of  killing  weeds,  but  more  than  this  is  unnecessary  and 
unprofitable  in  seasons  of  normal  rainfall ; and  it  is  much  better  actually  to 
enrich  the  soil  by  proper  applications  or  additions,  including  limestone  and 
organic  matter  (both  of  which  have  power  to  improve  the  physical  condition 
as  well  as  to  liberate  plant  food)  than  merely  to  hasten  soil  depletion  by  means 
of  excessive  cultivation. 

Permanent  Soil  Improvement 

The  best  and  most  profitable  methods  for  the  permanent  improvement  of 
the  common  soils  of  Illinois  are  as  follows: 

(1)  If  the  soil  is  acid,  apply  at  least  two  tons-  per  acre  of  ground  lime- 
stone, preferably  at  times  magnesian  limestone  (CaC03MgC03),  which  con- 
tains both  calcium  and  magnesium  and  has  slightly  greater  power  to  correct 
soil  acidity,  ton  for  ton,  than  the  ordinary  calcium  limestone  (CaC03) ; and 
continue  to  apply  about  two  tons  per  acre  of  ground  limestone  every  four  or 
five  years.  On  strongly  acid  soils,  or  on  land  being  prepared  for  alfalfa,  five 
tons  per  acre  of  ground  limestone  may  well  be  used  for  the  first  application. 

(2)  Adopt  a good  rotation  of  crops,  including  a liberal  use  of  legumes,  and 
increase  the  organic  matter  of  the  soil  either  by  plowing  under  the  legume  crops 
and  other  crop  residues  (straw  and  corn  stalks),  or  by  using  for  feed  and  bed- 
ding practically  all  the  crops  raised  and  returning  the  manure  to  the  land  with 
the  least  possible  loss.  No  one  can  say  in  advance  what  will  prove  to  be  the 
best  rotation  of  crops,  because  of  variation  in  farms  and  farmers,  and  in  prices 
for  produce,  but  the  following  are  suggested  to  serve  as  models  or  outlines: 

First  year,  corn. 

Second  year,  corn. 

Third  year,  wheat  or  oats  (with  clover  or  clover  and  grass). 

Fourth  year,  clover  or  clover  and  grass. 

Fifth  year,  wheat  and  clover  or  grass  and  clover. 

Sixth  year,  clover  or  clover  and  grass. 

Of  course  there  should  be  as  many  fields  as  there  are  years  in  the  rotation. 
In  grain  farming,  with  small  grain  grown  the  third  and  fifth  years,  most  of  the 
coarse  products  should  be  returned  to  the  soil,  and  the  clover  may  be  clipped 
and  left  on  the  land  (only  the  clover  seed  being  sold  the  fourth  and  sixth  years)  ; 
or,  in  live-stock  farming,  the  field  may  be  used  three  years  for  timothy  and 
clover  pasture  and  meadow  if  desired.  The  system  may  be  reduced  to  a five- 
year  rotation  by  cutting  out  either  the  second  or  the  sixth  year,  and  to  a four- 
year  system  by  omitting  the  fifth  and  sixth  years. 


LUIS] 


Bond  County 


53 


With  two  years  of  corn,  followed  by  oats  with  clover-seeding  the  third  year, 
and  by  clover  the  fourth  year,  all  produce  can  be  used  for  feed  and  bedding  if 
other  land  is  available  for  permanent  pasture.  Alfalfa  may  be  grown  on  a fifth 
field  for  four  or  eight  years,  which  is  to  be  alternated  with  one  of  the  four ; or 
the  alfalfa  may  be  moved  every  five  years,  and  thus  rotated  over  all  five  fields 
every  twenty-five  years. 

Other  four-year  rotations  more  suitable  for  grain  farming  are : 

Wheat  (and  clover),  corn,  oats,  and  clover;  or  corn  (and  clover),  cowpeas,  wheat,  and 
clover.  (Alfalfa  may  be  grown  on  a fifth  field  and  rotated  every  five  years,  the 
hay  being  sold.) 

Good  three-year  rotations  are; 

Corn,  oats,  and  clover;  corn,  wheat,  and  clover;  or  wheat  (and  clover),  corn  (and 
clover),  and  cowpeas,  in  which  two  cover  crops  and  one  regular  crop  of  legumes 
are  grown  in  three  years. 

A five-year  rotation  of  (1)  corn  (and  clover),  (2)  cowpeas,  (3)  wheat, 
(4)  clover,  and  (5)  wheat  (and  clover)  allows  legumes  to  be  seeded  four  times. 
Alfalfa  may  be  grown  on  a sixth  field  for  five  or  six  years  in  the  combination 
rotation,  alternating  between  two  fields  every  five  years,  or  rotating  over  all  the 
fields  if  moved  every  six  years. 

To  avoid  clover  sickness  it  may  sometimes  be  necessary  to  substitute  sweet 
clover  or  alsike  for  red  clover  in  about  every  third  rotation,  and  at  the  same 
time  to  discontinue  its  use  in  the  cover-crop  mixture.  If  the  corn  crop  is  not 
too  rank,  cowpeas  or  soybeans  may  also  be  used  as  a cover  crop  (seeded  at  the 
last  cultivation)  in  the  southern  part  of  the  state,  and,  if  necessary  to  avoid 
disease,  these  may  well  alternate  in  successive  rotations. 

For  easy  figuring  it  may  well  be  kept  in  mind  that  the  following  amounts 
of  nitrogen  are  required  for  the  produce  named: 

1 bushel  of  oats  (grain  and  straw)  requires  1 pound  of  nitrogen. 

1 bushel  of  corn  (grain  and  stalks)  requires  1%  pounds  of  nitrogen. 

1 bushel  of  wheat  (grain  and  straw)  requires  2 pounds  of  nitrogen. 

1 ton  of  timothy  requires  24  pounds  of  nitrogen. 

1 ton  of  clover  contains  40  pounds  of  nitrogen. 

1 ton  of  cowpeas  contains  43  pounds  of  nitrogen. 

1 ton  of  average  manure  contains  10  pounds  of  nitrogen. 

The  roots  of  clover  contain  about  half  as  much  nitrogen  as  the  tops,  and 
the  roots  of  cowpeas  contain  about  one-tenth  as  much  as  the  tops. 

Soils  of  moderate  productive  power  will  furnish  as  much  nitrogen  to  clover 
(and  two  or  three  times  as  much  to  cowpeas)  as  will  be  left  in  the  roots  and 
stubble.  In  grain  crops,  such  as  wheat,  corn,  and  oats,  about  two-thirds  of  the 
nitrogen  is  contained  in  the  grain  and  one- third  in  the  straw  or  stalks.  (See 
also  discussion  of  “The  Potassium  Problem,”  on  pages  following.) 

(3)  On  all  lands  deficient  in  phosphorus  (except  on  those  susceptible  to 
serious  erosion  by  surface  washing  or  gullying)  apply  that  element  in  consid- 
erably larger  amounts  than  are  required  to  meet  the  actual  needs  of  the  crops 
desired  to  be  produced.  The  abundant  information  thus  far  secured  shows  posi- 
tively that  fine-ground  natural  rock  phosphate  can  be  used  successfully  and  very 
profitably,  and  clearly  indicates  that  this  material  will  be  the  most  economical 
form  of  phosphorus  to  use  in  all  ordinary  systems  of  permanent,  profitable  soil 


54 


Soil  Report  No.  8 


[October, 


improvement.  The  first  application  may  well  be  one  ton  per  acre,  and  subse- 
quently about  one-half  ton  per  acre  every  four  or  five  years  should  be  applied, 
at  least  until  the  phosphorus  content  of  the  plowed  soil  reaches  2,000  pounds  per 
acre,  which  may  require  a total  application  of  from  three  to  five  or  six  tons  per 
acre  of  raw  phosphate  containing  121/2  percent  of  the  element  phosphorus. 

Steamed  bone  meal  and  even  acid  phosphate  may  be  used  in  emergencies, 
but  it  should  always  be  kept  in  mind  that  phosphorus  delivered  in  Illinois  costs 
about  3 cents  a pound  in  raw  phosphate  (direct  from  the  mine  in  carload  lots), 
but  10  cents  a pound  in  steamed  bone  meal,  and  about  12  cents  a pound  in  acid 
phosphate,  both  of  which  cost  too  much  per  ton  to  permit  their  common  purchase 
by  farmers  in  carload  lots,  which  is  not  the  case  with  limestone  or  raw  phos- 
phate. 

Phosphorus  once  applied  to  the  soil  remains  in  it  until  removed  in  crops, 
unless  carried  away  mechanically  by  soil  erosion.  (The  loss  by  leaching  is  only 
about  11/2  pounds  per  acre  per  annum,  so  that  more  than  150  years  would  be 
required  to  leach  away  the  phosphorus  applied  in  one  ton  of  raw  phosphate.) 

The  phosphate  and  limestone  may  be  applied  at  any  time  during  the  rota- 
tion, but  a good  method  is  to  apply  the  limestone  after  plowing  and  work  it  into 
the  surface  soil  in  preparing  the  seed  bed  for  wheat,  oats,  rye,  or  barley,  where 
clover  is  to  be  seeded ; while  phosphate  is  best  plowed  under  with  farm  manure, 
clover,  or  other  green  manures,  which  serve  to  liberate  the  phosphorus. 

(4)  Until  the  supply  of  decaying  organic  matter  has  been  made  adequate, 
on  the  poorer  types  of  upland  timber  and  gray  prairie  soils  some  temporary 
benefit  may  be  derived  from  the  use  of  a soluble  salt  or  a mixture  of  salts,  such 
as  kainit,  which  contains  both  potassium  and  magnesium  in  soluble  form  and 
also  some  common  salt  (sodium  chlorid).  About  600  pounds  per  acre  of  kainit 
applied  and  turned  under  with  the  raw  phosphate  will  help  to  dissolve  the  phos- 
phorus as  well  as  to  furnish  available  potassium  and  magnesium,  and  for  a few 
years  such  use  of  kainit  may  be  profitable  on  lands  deficient  in  organic  matter, 
but  the  evidence  thus  far  secured  indicates  that  its  use  is  not  absolutely  necessary 
and  that  it  will  not  be  profitable  after  adequate  provision  is  made  for  supplying 
decaying  organic  matter,  since  this  will  necessitate  returning  to  the  soil  the 
potassium  contained  in  the  crop  residues  from  grain  farming  or  the  manure 
produced  in  live-stock  farming,  and  will  also  provide  for  the  liberating  of-  potas- 
sium from  the  soil.  (Where  hay  or  straw  is  sold,  manure  should  be  bought.) 

On  soils  which  are  subject  to  surface  washing,  including  especially  the 
yellow  silt  loam  of  the  upland  timber  area,  and  to  some  extent  the  yellow-gray 
silt  loam  and  other  more  rolling  areas,  the  supply  of  minerals  in  the  subsurface 
and  subsoil  (which  gradually  renew  the  surface  soil)  tends  to  provide  for  a 
low-grade  system  of  permanent  agriculture  if  some  use  is  made  of  legume  plants, 
as  in  long  rotations  with  much  pasture,  because  both  the  minerals  and  nitrogen 
are  thus  provided  in  some  amount  almost  permanently;  but  where  such  lands 
are  farmed  under  such  a system,  not  more  than  two  or  three  grain  crops  should 
be  grown  during  a period  of  ten  or  twelve  years,  the  land  being  kept  in  pasture 
most  of  the  time;  and  where  the  soil  is  acid  a liberal  use  of  limestone,  as  top- 
dressings  if  necessary,  and  occasional  reseeding  with  clovers  will  benefit  both  the 
pasture  and  indirectly  the  grain  crops. 


Bond  County 


55 


191S~\ 


Advantage  of  Crop  Rotation  and  Permanent  Systems 

It  should  be  noted  that  clover  is  not  likely  to  be  well  infected  with  the 
clover  bacteria  during  the  first  rotation  on  a given  farm  or  field  where  it  has 
not  been  grown  before  within  recent  years;  but  even  a partial  stand  of  clover 
the  first  time  will  probably  provide  a thousand  times  as  many  bacteria  for  the 
next  clover  crop  as  one  could  afford  to  apply  in  artificial  inoculation,  for  a single 
root-tubercle  may  contain  a million  bacteria  developed  from  one  during  the  sea- 
son’s growth. 

This  is  only  one  of  several  advantages  of  the  second  course  of  the  rotation 
over  the  first  course.  Thus  the  mere  practice  of  crop  rotation  is  an  advantage, 
especially  in  helping  to  rid  the  land  of  insects  and  foul  grass  and  weeds.  The 
clover  crop  is  an  advantage  to  subsequent  crops  because  of  its  deep-rooting  char- 
acteristic. The  larger  applications  of  organic  manures  (made  possible  by  the 
larger  crops)  are  a great  advantage ; and  in  systems  of  permanent  soil  improve- 
ment, such  as  are  here  advised  and  illustrated,  more  limestone  and  more  phos- 
phorus are  provided  than  are  needed  for  the  meager  or  moderate  crops  pro- 
duced during  the  first  rotation,  and  consequently  the  crops  in  the  second  rota- 
tion have  the  advantage  of  such  accumulated  residues  (well  incorporated  with 
the  plowed  soil)  in  addition  to  the  regular  applications  made  during  the  second 
rotation. 

This  means  that  these  systems  tend  positively  toward  the  making  of  richer 
lands.  The  ultimate  analyses  recorded  in  the  tables  give  the  absolute  invoice 
of  these  Illinois  soils.  They  show  that  most  of  them  are  positively  deficient  only 
in  limestone,  phosphorus,  and  nitrogenous  organic  matter ; and  the  accumulated 
information  from  careful  and  long-continued  investigations  in  different  parts  of 
the  United  States  clearly  establishes  the  fact  that  in  general  farming  these  essen- 
tials can  be  supplied  with  greatest  economy  and  profit  by  the  use  of  ground  nat- 
ural limestone,  very  finely  ground  natural  rock  phosphate,  and  legume  crops  to 
be  plowed  under  directly  or  in  farm  manure.  On  normal  soils  no  other  applica- 
tions are  absolutely  necessary,  but,  as  already  explained,  the  addition  of  some 
soluble  salt  in  the  beginning  of  a system  of  improvement  on  some  of  these  soils 
produces  temporary  benefit,  and  if  some  inexpensive  salt,  such  as  kainit,  is  used, 
it  may  produce  sufficient  increase  to  more  than  pay  the  added  cost. 

The  Potassium  Problem 

As  reported  in  Illinois  Bulletin  123,  where  wheat  has  been  grown  every  year 
for  more  than  half  a century  at  Rothamsted,  England,  exactly  the  same  increase 
was  produced  (5.6  bushels  per  acre),  as  an  average  of  the  first  24  years,  whether 
potassium,  magnesium,  or  sodium  was  applied,  the  rate  of  application  per  annum 
being  200  pounds  of  potassium  sulfate  and  molecular  equivalents  of  magnesium 
sulfate  and  sodium  sulfate.  As  an  average  of  60  years  (1852  to  1911),  the  yield 
of  wheat  was  12.7  bushels  on  untreated  land  and  23.3  bushels  where  86  pounds 
of  nitrogen  and  29  pounds  of  phosphorus  per  acre  per  annum  were  applied. 
As  further  additions,  85  pounds  of  potassium  raised  the  yield  to  31.3  bushels; 
52  pounds  of  magnesium  raised  it  to  29.2  bushels;  and  50  pounds  of  sodium  raised 
it  to  29.5  bushels.  Where  potassium  was  applied,  the  wheat  crop  removed  an- 


56 


Soil  Report  No.  8 


[' October , 


nually  an  average  of  40  pounds  of  that  element  in  the  grain  and  straw,  or  three 
times  as  much  as  would  be  removed  in  the  grain  only  for  such  crops  as  are 
suggested  in  Table  A.  The  Rothamsted  soil  contained  an  abundance  of  lime- 
stone, but  no  organic  matter  was  provided  except  the  little  in  the  stubble  and 
roots  of  the  wheat  plants. 

On  another  field  at  Rothamsted  the  average  yield  of  barley  for  60  years 
(1852  to  1911)  was  14.2  bushels  on  untreated  land,  38.1  bushels  where  43  pounds 
of  nitrogen  and  29  pounds  of  phosphorus  were  applied  per  acre  per  annum; 
while  the  further  addition  of  85  pounds  of  potassium,  19  pounds  of  magnesium, 
and  14  pounds  of  sodium  (all  in  sulfates)  raised  the  average  yield  to  41.5 
bushels.  Where  only  70  pounds  of  sodium  were  applied  in  addition  to  the 
nitrogen  and  phosphorus,  the  average  was  43.0  bushels.  Thus,  as  an  average 
of  60  years,  the  use  of  sodium  produced  1.8  bushels  less  wheat  and  1.5  bushels 
more  barley  than  the  use  of  potassium,  with  both  grain  and  straw  removed  and 
no  organic  manures  returned. 

In  recent  years  the  effect  of  potassium  is  becoming  much  more  marked  than 
that  of  sodium  or  magnesium,  on  the  wheat  crop ; but  this  must  be  expected  to 
occur  in  time  where  no  potassium  is  returned  in  straw  or  manure,  and  no  pro- 
vision made  for  liberating  potassium  from  the  supply  still  remaining  in  the  soil. 
If  the  wheat  straw,  which  contains  more  than  three-fourths  of  the  potassium 
removed  in  the  wheat  crop  (see  Table  A),  were  returned  to  the  soil,  the  neces- 
sity of  purchasing  potassium  in  a good  system  of  farming  on  such  land  would 
be  at  least  very  remote,  for  the  supply  would  be  adequately  maintained  by 
the  actual  amount  returned  in  the  straw,  together  with  the  additional  amount 
which  would  be  liberated  from  the  soil  by  the  action  of  decomposition  products. 

While  about  half  the  potassium,  nitrogen,  and  organic  matter,  and  about 
one-fourth  the  phosphorus  contained  in  manure  is  lost  by  three  or  four  months’ 
exposure  in  the  ordinary  pile  in  the  barn  yard,  there  is  practically  no  loss 
if  plenty  of  absorbent  bedding  is  used  on  cement  floors,  and  if  the  manure  is 
hauled  to  the  field  and  spread  within  a day  or  two  after  it  is  produced.  Again, 
while  in  average  live-stock  farming  the  animals  destroy  two-thirds  of  the  or- 
ganic matter  and  retain  one-fourth  of  the  nitrogen  and  phosphorus  from  the 
food  they  consume,  they  retain  less  than  one-tenth  of  the  potassium ; so  that  the 
actual  loss  of  potassium  in  the  products  sold  from  the  farm,  either  in  grain 
farming  or  in  live-stock  farming,  is  wholly  negligible  on  land  containing  25,000 
pounds  or  more  of  potassium  in  the  surface  6%  inches. 

The  removal  of  one  inch  of  soil  per  century  by  surface  washing  (which  is 
likely  to  occur  wherever  there  is  satisfactory  surface  drainage  and  frequent  cul- 
tivation) will  permanently  maintain  the  potassium  in  grain  farming  by  re- 
newal from  the  subsoil,  provided  one-third  of  the  potassium  is  removed  by  crop- 
ping before  the  soil  is  carried  away. 

From  all  these  facts  it  will  be  seen  that  the  potassium  problem  is  not  one 
of  addition  but  of  liberation;  and  the  Rothamsted  records  show  that  for  many 
years  other  soluble  salts  have  practically  the  same  power  as  potassium  to  increase 
crop  yields  in  the  absence  of  sufficient  decaying  organic  matter.  Whether  this 


Bond  County 


57 


19  IS] 

action  relates  to  supplying  or  liberating  potassium  for  its  own  sake,  or  to  the 
power  of  the  soluble  salt  to  increase  the  availability  of  phosphorus  or  other  ele- 
ments, is  not  known,  but  where  much  potassium  is  removed,  as  in  the  entire  crops 
at  Rothamsted,  with  no  return  of  organic  residues,  probably  the  soluble  salt 
functions  in  both  ways. 

As  an  average  of  112  separate  tests  conducted  in  1907,  1908,  1909,  and  1910 
on  the  Fairfield  experiment  field,  an  application  of  200  pounds  of  potassium 
sulfate,  containing  85  pounds  of  potassium  and  costing  $5.10,  increased  the  yield 
of  corn  by  9.3  bushels  per  acre ; while  600  pounds  of  kainit,  containing  only  60 
pounds  of  potassium  and  costing  $4,  gave  an  increase  of  10.7  bushels.  Thus,  at 
40  cents  a bushel  for  corn,  the  kainit  paid  for  itself ; but  these  results,  like  those 
at  Rothamsted,  were  secured  where  no  adequate  provision  had  been  made  for 
decaying  organic  matter. 

Additional  experiments  at  Fairfield  included  an  equally  complete  test  with 
potassium  sulfate  and  kainit  on  land  to  which  8 tons  per  acre  of  farm  manure 
were  applied.  As  an  average  of  112  tests  with  each  material,  the  200  pounds 
of  potassium  sulfate  increased  the  yield  of  corn  by  1.7  bushels,  while  the  600 
pounds  of  kainit  also  gave  an  increase  of  1.7  bushels.  Thus,  where  organic 
manure  was  supplied,  very  little  effect  was  produced  by  the  addition  of  either' 
potassium  sulfate  or  kainit;  in  part  perhaps  because  the  potassium  removed  in 
the  crops  is  mostly  returned  in  the  manure  if  properly  cared  for,  and  perhaps 
in  larger  part  because  the  decaying  organic  matter  helps  to  liberate  and  hold 
in  solution  other  plant-food  elements,  especially  phosphorus. 

In  laboratory  experiments  at  the  Illinois  Experiment  Station,  it  has  been 
shown  by  chemical  analysis  that  potassium  salts  and  most  other  soluble  salts 
increase  the  solubility  of  the  phosphorus  in  soil  and  in  rock  phosphate;  also 
that  the  addition  of  glucose  with  rock  phosphate  in  pot-culture  experiments 
increases  the  availability  of  the  phosphorus,  as  measured  by  plant  growth,  altho 
the  glucose  consists  only  of  carbon,  hydrogen,  and  oxygen,  and  thus  contains 
no  plant  food  of  value. 

If  we  remember  that,  as  an  average,  live  stock  destroy  two-thirds  of  the  or- 
ganic matter  of  the  food  they  consume,  it  it  easy  to  determine  from  Table  A that 
more  organic  matter  will  be  supplied  in  a proper  grain  system  than  in  a strictly 
live-stock  system;  and  the  evidence  thus  far  secured  from  older  experiments  at 
the  University  and  at  other  places  in  the  state  indicates  that  if  the  corn  stalks, 
straw,  clover,  etc.,  are  incorporated  with  the  soil  as  soon  as  practicable  after  they 
are  produced  (which  can  usually  be  done  in  the  late  fall  or  early  spring),  there 
is  little  or  no  difficulty  in  securing  sufficient  decomposition  in  our  humid  climate 
to  avoid  serious  interference  with  the  capillary  movement  of  the  soil  moisture, 
a common  danger  from  plowing  under  too  much  coarse  manure  of  any  kind  in 
the  late  spring  of  a dry  year. 

If,  however,  the  entire  produce  of  the  land  is  sold  from  the  farm,  as  in  hay 
farming  or  when  both  grain  and  straw  are  sold,  of  course  the  draft  on  potas- 
sium will  then  be  so  great  that  in  time  it  must  be  renewed  by  some  sort  of  appli- 
cation. As  a rule,  farmers  following  this  practice  ought  to  secure  manure  from 
town,  since  they  furnish  the  bulk  of  the  material  out  of  which  manure  is  pro- 
duced. 


58 


Soil  Report  No.  8 


[October, 


Calcium  and  Magnesium 

When  measured  by  the  actual  crop  requirements  for  plant  food,  magnesium 
and  calcium  are  more  limited  in  some  Illinois  soils  than  potassium.  But  with 
these  elements  we  must  also  consider  the  loss  by  leaching.  As  an  average  of  90 
analyses1  of  Illinois  well-waters  drawn  chiefly  from  glacial  sands,  gravels,  or  till, 
3 million  pounds  of  water  (about  the  average  annual  drainage  per  acre  for 
Illinois)  contained  11  pounds  of  potassium,  130  of  magnesium,  and  330  of  cal- 
cium. These  figures  are  very  significant,  and  it  may  be  stated  that  if  the  plowed 
soil  is  well  supplied  with  the  carbonates  of  magnesium  and  calcium,  then  a very 
considerable  proportion  of  these  amounts  will  be  leached  from  that  stratum. 
Thus  the  loss  of  calcium  from  the  plowed  soil  of  an  acre  at  Rothamsted,  England, 
where  the  soil  contains  plenty  of  limestone,  has  averaged  more  than  300  pounds 
a year  as  determined  by  analyzing  the  soil  in  1865  and  again  in  1905.  Prac- 
tically the  same  amount  of  calcium  was  found,  by  analyses,  in  the  Rothamsted 
drainage  waters. 

Common  limestone,  which  is  calcium  carbonate  (CaC03),  contains,  when 
pure,  40  percent  of  calcium,  so  that  800  pounds  of  limestone  are  equivalent  to 
320  pounds  of  calcium.  Where  10  tons  per  acre  of  ground  limestone  were 
applied  at  Edgewood,  Illinois,  the  average  annual  loss  during  the  next  ten  years 
amounted  to  790  pounds  per  acre.  The  definite  data  from  careful  investigations 
seem  to  be  ample  to  justify  the  conclusion  that  where  limestone  is  needed  at 
least  2 tons  per  acre  should  be  applied  every  4 or  5 years. 

It  is  of  interest  to  note  that  thirty  crops  of  clover  of  four  tons  each  would 
require  3,510  pounds  of  calcium,  while  the  most  common  prairie  land  of  southern 
Illinois  contains  only  3,420  pounds  of  total  calcium  in  the  plowed  soil  of  an 
acre.  (See  Soil  Report  No.  1.)  Thus  limestone  has  a positive  value  on  some 
soils  for  the  plant  food  which  it  supplies,  in  addition  to  its  value  in  correcting 
soil  acidity  and  in  improving  the  physical  condition  of  the  soil.  Ordinary  lime- 
stone (abundant  in  the  southern  and  western  parts  of  the  state)  contains  nearly 
800  pounds  of  calcium  per  ton;  while  a good  grade  of  dolomitic  limestone  (the 
more  common  limestone  of  northern  Illinois)  contains  about  400  pounds  of  cal- 
cium and  300  pounds  of  magnesium  per  ton.  Both  of  these  elements  are  fur- 
nished in  readily  available  form  in  ground  dolomitic  limestone. 

Reported  by  Doctor  Bartow  and  associates,  of  the  Illinois  State  Water  Survey. 


UNIVERSITY  OF  ILLINOIS 


Agricultural  Experiment  Station 


SOIL  REPORT  NO.  9 


LAKE  COUNTY  SOILS 


By  CYRIL  G.  HOPKINS,  J.  G.  MOSIER, 
E.  VAN  ALSTINE,  and  F.  W.  GARRETT 


URBANA,  ILLINOIS,  APRIL,  1915 


State  Advisory  Committee  on  Soil  Investigations 

Ralph  Allen,  Delavan  A.  N.  Abbott,  Morrison 

F.  I.  Mann,  Gilman  J.  P.  Mason,  Elgin 

C.  V.  Gregory,  538  S.  Clark  Street,  Chicago 

Agricultural  Experiment  Station  Staff  on  Soil  Investigations 
Eugene  Davenport,  Director 


Cyril  G.  Hopkins,  Chief 
Soil  Survey — 

J.  G.  Mosier,  Chief 
A.  F.  Gustafson,  Associate 
S.  Y.  Holt,  Associate 
H.  W.  Stewart,  Associate 
H.  C.  Wheeler,  Associate 

F.  A.  Fisher,  Assistant 

F.  M.  W.  Wascher,  Assistant 
R.  W.  Dickenson,  Assistant 

G.  E.  Gentle,  Assistant 
O.  I.  Ellis,  Assistant 

H.  A.  deWerff,  Assistant 
E.  F.  Torgerson,  Assistant 

Soil  Analysis — 

E.  Van  Alstine,  Associate 
J.  P.  Aumer,  Associate 
W.  H.  Sachs,  Associate 
Gertrude  Niederman,  A_3sista: 
W.  R.  Leighty,  Assistant 
C.  B.  Clevenger,  Assistant 


Agronomy  and  Chemistry 
Soil  Experiment  Fields — 

J.  E.  Whitchurch,  Associate 

E.  E.  Hoskins,  Associate 

F.  C.  Bauer,  Associate 
F.  W.  Garrett,  Assistant 
H.  C.  Gilkerson,  Assistant 

H.  F.  T.  Fahrnkopf,  Assistant 
H.  J.  Snider,  Assistant 


Soil  Biology — 

A.  L.  Whiting,  Associate 
W.  R.  Schoonover,  Assistant 

Soils  Extension — 

C.  C.  Logan,  Associate 


INTRODUCTORY  NOTE 


About  two-thirds  of  Illinois  lies  in  the  corn  belt,  where  most  of  the  prairie 
lands  are  black  or  dark  brown  in  color.  In  the  southern  third  of  the  state,  the 
prairie  soils  are  largely  of  a gray  color.  This  region  is  better  known  as  the 
wheat  belt,  altho  wheat  is  often  grown  in  the  corn  belt  and  com  is  also  a com- 
mon crop  in  the  wheat  belt. 

Moultrie  county,  representing  the  corn  belt ; Clay  county,  which  is  fairly 
representative  of  the  wheat  belt  ; and  Hardin  county,  which  is  taken  to  repre- 
sent the  unglaciated  area  of  the  extreme  southern  part  of  the  state,  were  se- 
lected for  the  first  Illinois  Soil  Reports  by  counties.  While  these  three  county 
soil  reports  were  sent  to  the  fetation’s  entire  mailing  list  within  the  state,  sub- 
sequent reports  are  sent  only  to  those  on  the  mailing  list  who  are  residents  of  the 
county  concerned,  and  to  any  one  else  upon  request. 

Each  county  report  is  intended  to  be  as  nearly  complete  in  itself  as  it 
is  practicable  to  make  it,  and,  even  at  the  expense  of  some  repetition,  each 
will  contain  a general  discussion  of  important  fundamental  principles  in  order 
to  help  the  farmer  and  landowner  understand  the  meaning  of  the  soil  fer- 
tility invoice  for  the  lands  in  which  he  is  interested.  In  Soil  Report  No.  1, 
“Clay  County  Soils,”  this  discussion  serves  in  part  as  an  introduction,  while 
in  this  and  other  reports,  it  will  be  found  in  the  Appendix ; but  if  necessary  it 
should  be  read  and  studied  in  advance  of  the  report  proper. 


LAKE  COUNTY  SOILS 

By  CYRIL  G.  HOPKINS,  J.  G.  HOSIER.  E.  VAN  ALSTINE,  and  P.  W.  GARRETT 


Lake  county  is  located  in  the  northeast  corner  of  Illinois  in  the  late  Wis- 
consin glaciation,  and  is  covered  with  a deposit  of  material  made  by  the  Lake 
Michigan  glacier  during  its  two  stages.  The  topography  of  the  county,  tho  quite 
rolling  in  many  parts,  is  due  almost  entirely  to  the  very  irregular  deposition  of 
material  by  this  glacier.  Two  distinct  morainal  areas  occur.  The  one  known  as 
the  Lake  Border  morainic  system  occupies  the  eastern  part  of  the  county  and 
extends  southward  in  the  form  of  two  low  ridges,  one  near  the  lake  and  an- 
other just  east  of  the  Des  Plaines  river;  the  other,  the  Valparaiso  morainic  sys- 
tem, occupies  the  western  part  of  the  county.  The  latter  reaches  an  altitude 
of  about  300  feet  above  Lake  Michigan.  These  morainic  areas  are  marked  by 
large  numbers  of  kettle-holes,  or  basin-like  depressions,  that  in  the  most  rolling 
parts  sometimes  have  a depth  of  75  feet.  Numerous  lakes  are  found  in  the 
Valparaiso  morainic  system. 

The  drift  deposited  by  the  Lake  Michigan  glacier  over  the  county  has  a 
minimum  depth  of  probably  150  feet,  while  the  thicker  deposits  are  between  300 
and  400  feet.  Leverett,  in  Monograph  38  of  the  United  States  Geological  Sur- 
vey, states  that  the  deposit  of  drift  averages  more  than  200  feet  in  thickness  over 
the  county..  Borings  indicate  the  presence  of  still  older  glacial  drift  beneath 
that  of  the  late  Wisconsin. 


Physiography 

Lake  county  is  divided  into  two  distinct  drainage  systems — one  sloping 
into  Lake  Michigan  and  comprizing  probably  not  more  than  one-fifteenth  of  the 
total  area  of  the  county,  and  a second,  drained  by  the  Des  Plaines  and  the  Fox 
rivers,  into  the  Illinois.  The  large  number  of  lakes  and  swamps  in  this  county 
indicate  very  late  drainage  systems,  so  late  that  practically  all  of  the  lowland 
is  occupied  either  by  lakes  or  by  swamps.  The  streams  have  not  had  time  to  form 
valleys  sufficiently  deep  for  draining  these  low  areas.  There  are  about  fifty  lakes 
in  the  county  large  enough  to  be  shown  on  the  soil  map,  many  of  which  are  sur- 
rounded, or  nearly  so,  by  swamps  containing  deposits  of  peat. 

The  altitudes  of  some  places  in  the  county  above  sea  level  are  as  follows: 
Antioch,  770  feet;  Aptakisic,~682 ; Diamond  Lake,  760;  Fox  Lake,  745;  Gilmer, 
810;  Gray’s  Lake,  799 ; Gurnee,  677;  Highland  Park,  691;  Lake  Bluff,  683;  Lake 
Villa,  796;  Lake  Zurich,  873;  Leithton,  723;  Libertyville,  670;  Loon  Lake,  783  ; 
Prairie  View,  694;  Rodont,  676;  Russell,  677 ; Volo,  890;  Wadsworth,  673;  War- 


l 


Soil  Report  No.  9 


[April, 


renton,  710;  Waukegan  (C.  & N.  W.),  596.  A bench  mark  on  the  east  entrance 
of  the  courthouse  at  Waukegan  is  668.4  feet.  The  mean  altitude  of  the  water 
of  Lake  Michigan  is  581  feet  above  sea  level. 

Soil  Material  and  Soil  Types 

The  Lake  Michigan  glacier  left  a deposit  of  boulder  clay  (a  mixture  of 
boulders,  gravel,  sand,  silt,  and  clay),  which  has  been  transformed  into  soil  in 
some  places ; but  the  larger  part  of  the  county  subsequently  received  a shallow 
deposit  of  12  to  40  inches  of  loessial  material  formed  from  the  fine  rock  flour 
produced  by  the  grinding  action  of  the  glacier.  This  has  been  reworked  by  the 
wind  and  water  and  now  covers  the  level  and  less  rolling  areas  to  an  average 
depth  of  16  to  20  inches.  Beneath  this  is  often  found  a stratum  a few  inches 
in  thickness  which  contains  a great  many  gravel,  indicating  the  washing  out  of 
the  fine  material  before  the  loess  was  deposited.  From  Waukegan  to  the  state 
line  a deposit  has  been  formed  by  Lake  Chicago  which  consists  of  a series  of 
sand  ridges  only  a few  rods  apart  that  have  very  little  argricultural  use.  Be- 
tween these  ridges  peat  deposits  are  frequently  found. 


Table  1. — Soil  Types  of  Lake  County 


Soil 

type 

No. 

Name  of  type 

Area  in 
square 
miles 

Area 

in 

acres 

Percent 
of  total 
area 

1026  l 

1226  f 
1060  | 
1260  f 

(a)  Upland  Prairie  Soils  (page  23) 

Brown  silt  loam  

1 

Brown  sandy  loam  

137.50 

2.88 

88  001 
1 844 

28.48 

.60 

1034  j 

1234  .f 

1035 

1235  f 
1064 
1064.4 
1081  ) 
1281  \ 
1090  l 
1290  S 

(b)  Upland  Timber  Soils  (page  25) 

Yellow-gray  silt  loam  

lYellow  silt  loam  

Yellow-gray  sandy  loam 

Yellow-gray  sandy  loam  on  gravel 

Dune  sand  

Gravelly  loam  

196.01 

38.50 

.76 

1.48 

1.47 

.96 

125  447 

24  639 
488 
944 

938 

611 

40.59 

7.98 

.16 

.30 

.30 

.20 

1527 

(c)  Terrace  Soils  (page  30) 

Brown  silt  loam  over  gravel 

1.85 

1 184 

.38 

1564.4 

Yellow-gray  sandy  loam  on  gravel 

2.25 

1 440 

.47 

1560.4 

Brown  sandy  loam  on  gravel 

2.40 

1 539 

:50 

1590.4 

Gravelly  loam  on  gravel  

.28 

179 

.06 

1401 

(d)  Swamp  and  Bottom-Land  Soils  (page  32) 

Deep  peat  

38.10 

24  382 

7.89 

1402 

Medium  peat  on  clay 

1.00 

640 

.21 

1402.2 

Medium  peat  on  sand . ! 

.44 

284 

.09 

1403 

Shallow  peat  on  clay 

.58 

371 

.12 

1410 

Peaty  loam  

2.35 

1 504 

.49 

1450 

Black  mixed  loam 

19.72 

12  622 

4.09 

1454 

Mixed  loam  (bottom  land) 

8.51 

5 446 

1.76 

1482 

Beach  sand  (mixed  sand  and  peat) 

7.79 

4 988 

1.61 

(e)  Miscellaneous  (page  38) 

Lakes  

17.99 

11  512 

3.72 

Total  

482.82 

309  003 

100.00 

Lake  County 


3 


ID  15] 


The  soils  of  Lake  county  are  divided  into  the  following  classes: 

(1)  Upland  prairie  soils,  usually  rich  in  organic  matter.  These  were  cov- 
ered originally  with  prairie  grasses,  the  partially  decayed  roots  of  which  have 
been  the  source  of  the  organic  matter.  The  flat,  poorly  drained  areas  contain 
the  highest  amounts  of  organic  matter,  owing  to  the  more  luxuriant  growth  of 
grasses  there  and  the  better  chance  for  their  preservation  by  the  excessive  mois- 
ture in  the  soil. 

(2)  Upland  timber  soils,  including  nearly  all  upland  areas  that  were  for- 
merly covered  with  forests.  These  soils  contain  much  less  organic  matter  than 
the  soils  of  the  prairies  because  the  large  roots  of  dead  trees  and  the  surface 
accumulations  of  leaves,  twigs,  and  fallen  trees  were  burned  by  forest  fires,  or 
suffered  almost  complete  decay,  instead  of  being  incorporated  with  the  soil. 

(3)  Terrace  soils,  which  include  bench  lands,  or  second  bottom  lands,  that 
were  formed  at  the  time  of  the  melting  of  the  glacier,  when  the  valleys  were 
flooded  and  the  streams  overloaded  with  coarse  sediment.  Deposits  of  gravel 
were  formed  which  later  have  been  cut  thru  in  part  by  the  streams  during  their 
ordinary  stages.  These  benches  form  soil  types  that  are  usually  underlain  by 
gravel  or  sand. 

(4)  Swamp  and  bottom-land  soils,  which  include  the  overflow  lands  or 
flood  plains  along  the  streams,  the  swamps  around  some  of  the  lakes,  the  poorly 
drained  lowlands,  and  the  area  of  sand  beaches  deposited  by  Lake  Chicago. 

Table  1 shows  the  area  of  each  type  of  soil  in  Lake  county  in  square  miles 
and  in  acres,  and  its  percentage  of  the  total  area:  It  will  be  noted  that  the  yellow- 
gray  silt  loam,  or  undulating  timber  land,  occupies  the  larger  part  of  the  county. 
The  accompanying  map  shows  the  location  and  boundary  lines  of  every  type 
of  soil  in  the  county,  even  down  to  areas  of  a few  acres. 

THE  INVOICE  AND  INCREASE  OF  FERTILITY  IN  LAKE 
COUNTY  SOILS 

Soil  Analysis 

In  order  to  avoid  confusion  in  applying  in  a practical  way  the  technical 
information  contained  in  this  report,  the  results  are  given  in  the  most  simplified 
form.  The  composition  reported  for  a given  soil  type  is,  as  a rule,  the  average 
of  many  analyses,  which,  like  most  things  in  nature,  show  more  or  less  variation ; 
but  for  all  practical  purposes  the  average  is  most  trustworthy  and  sufficient. 
(See  Bulletin  123,  which  reports  the  general  soil  survey  of  the  state,  together 
with  many  hundred  individual  analyses  of  soil  samples  representing  twenty-five 
of  the  most  important  and  most  extensive  soil  types  in  the  state.) 

The  chemical  analysis  of  the  soil  gives  the  invoice  of  fertility  actually  pres- 
ent in  the  soil  strata  sampled  and  analyzed,  but,  as  explained  in  the  Appendix, 
the  rate  of  liberation  is  governed  by  many  factors.  Also,  as  there  stated,  prob- 
ably no  agricultural  fact  is  more  generally  known  by  farmers  and  landowners 
than  that  soils  differ  in  productive  power.  Even  tho  plowed  alike  and  at  the 
same  time,  prepared  the  same  way,  planted  the  same  day  with  the  same  kind 
of  seed,  and  cultivated  alike,  watered  by  the  same  rains  and  warmed  by  the 
same  sun,  nevertheless  the  best  acre  may  produce  twice  as  large  a crop  as  the 


4 


Soil  Report  No.  9 


[April, 


poorest  acre  on  the  same  farm,  if  not,  indeed,  in  the  same  field;  and  the  fact 
should  be  repeated  and  emphasized  that  the  productive  power  of  normal  soil 
in  humid  sections  depends  upon  the  stock  of  plant  food  contained  in  the  soil 
and  upon  the  rate  at  which  it  is  liberated. 

The  fact  may  be  repeated,  too,  that  crops  are  not  made  out  of  nothing. 
They  are  composed  of  ten  different  elements  of  plant  food,  every  one  of  which 
is  absolutely  essential  for  the  growth  and  formation  of  every  agricultural  plant. 
Of  these  ten  elements  of  plant  food,  only  two  (carbon  and  oxygen)  are  secured 
from  the  air  by  all  plants,  only  one  (hydrogen)  from  water,  while  seven  are 
secured  from  the  soil.  Nitrogen,  one  of  these  seven  elements  secured  from  the 
soil  by  all  plants,  may  also  be  secured  from  the  air  by  one  class  of  plants 
(legumes)  in  case  the  amount  liberated  from  the  soil  is  insufficient.  But  even 
the  leguminous  plants  (which  include  the  clovers,  peas,  beans,  alfalfa,  and 
vetches),  in  common  with  other  agricultural  plants,  secure  from  the  soil  alone 
six  elements  (phosphorus,  potassium,  magnesium,  calcium,  iron,  and  sulfur)  and 
also  utilize  the  soil  nitrogen  so  far  as  it  becomes  soluble  and  available  during 
their  period  of  growth. 

Table  A in  the  Appendix  shows  the  requirements  of  large  crops  for  the  five 
most  important  plant-food  elements  which  the  soil  must  furnish.  (Iron  and 
sulfur  are  supplied  normally  from  natural  sources  in  sufficient  abundance,  com- 
pared with  the  amounts  needed  by  plants,  so  that  they  are  never  known  to  limit 
the  yield  of  common  farm  crops.) 

In  Table  2 are  reported  the  amounts  of  organic  carbon  (the  best  measure  of 
the  organic  matter)  and  the  total  amounts  of  the  five  important  elements  of  plant 
food  contained  in  2 million  pounds  of  the  surface  soil  of  each  type, — the  plowed 
soil  of  an  acre  about  6%  inches  deep.  In  addition,  the  table  shows  the  amount 
of  limestone  present,  if  any,  or  the  soil  acidity  as  measured  by  the  amount  of 
limestone  required  to  neutralize  the  acidity  existing  in  the  soil. 

The  soil  to  the  depth  indicated  includes  at  least  as  much  as  is  ordinarily 
turned  with  the  plow,  and  represents  that  part  with  which  the  farm  manure, 
limestone,  phosphate,  or  other  fertilizer  applied  in  soil  improvement  is  incor- 
porated. It  is  the  soil  stratum  that  must  be  depended  upon  in  large  part  to 
furnish  the  necessary  plant  food  for  the  production  of  crops,  as  will  be  seen  from 
the  information  given  in  the  Appendix.  Even  a rich  subsoil  has  little  or  no 
value  if  it  lies  beneath  a worn-out  surface,  for  the  weak,  shallow-rooted  plants 
will  be  unable  to  reach  the  supply  of  plant  food  in  the  subsoil.  If,  however, 
the  fertility  of  the  surface  soil  is  maintained  at  a high  point,  then  the  plants, 
with  a vigorous  start  from  the  rich  surface  soil,  can  draw  upon  the  subsurface 
and  subsoil  for  a greater  supply  of  plant  food. 

By  easy  computation  it  will  be  found  that  the  most  common  prairie  soil  of 
Lake  county  does  not  contain  more  than  enough  total  nitrogen  in  the  plowed 
soil  for  the  production  of  maximum  crops  for  fifteen  rotations  (60  years),  while 
the  still  more  extensive  upland  timber  soil  (yellow-gray  silt  loam)  contains  only 
about  one-third  as  much  nitrogen  as  the  prairie  land,  or  sufficient  for  only 
eighteen  100-bushel  crops  of  corn,  grain,  and  stalks. 

With  respect  to  phosphorus,  the  condition  differs  only  in  degree,  half  the 
soil  area  of  the  county  containing  no  more  of  that  element  than  would  be  re- 


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MAP  OF  LAKE  COUNTY 


library 

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1915 ] 


Lake  County 


auired  for  ten  crop  rotations  if  such  yields  were  secured  as  are  suggested  in 
Table  A of  the  Appendix.  It  will  be  seen  from  the  same  table  that  in  the  case 
of  the  cereals  about  three-fourths  of  the  phosphorus  taken  from  the  soil  is  de- 
posited in  the  grain,  while  only  one-fourth  remains  in  the  straw  or  stalks. 

On  the  other  hand,  the  potassium  in  the  most  common  soil  type  is  sufficient 
for  36  centuries  if  only  the  grain  is  sold,  or  for  560  years  even  if  the  total  crops 
should  be  removed  and  nothing  returned.  The  corresponding  figures  are  about 
2,300  and  540  years  for  magnesium,  and  about  7,800  and  200  years  for  calcium. 
Thus,  when  measured  by  the  actual  crop  requirements  for  plant  food,  potassium 
is  no  more  limited  than  magnesium  and  calcium;  and  as  explained  in  the  Ap- 
pendix, with  magnesium,  and  more  especially  with  calcium,  we  must  also  con- 
sider the  fact  that  loss  by  leaching  is  far  greater  than  by  cropping. 

These  general  statements  relating  to  the  total  quantities  of  plant  food  in 
the  plowed  soil  of  the  most  prevalent  type  in  the  county  certainly  emphasize 
the  fact  that  the  supplies  of  some  of  these  necessary  elements  of  fertility  are 
extremely  limited  when  measured  by  the  needs  of  large  crop  yields  for  even  one 
or  two  generations  of  people. 


Table  2. — Fertility  in  the  Soils  op  Lake  County,  Illinois 


Average  pounds  per  acre  in  two  million  pounds  of  surface  soil  (about  0 to  6%  inches) 


Soil 

type 


Soil  type 


| Total  Total 

Total 

si  nitro-  phos- 

potas- 

1  gen  phorus 

sium 

Lime- 

stone 

present 


Soil 

acidity 


Upland  Prairie  Soils 


1226 

1 Brown 

silt  loam 

89  950 

7 490  1 

430(46 

930  12 

680 

13  300 

50 

1060 

| Brown 

sandy  loam 

8 300| 

640, 

420  25 

200  ( 2 

680 

5 020 

40 

Upland  Timber  Soils 


1234 

Yellow-gray  silt  loam. . . 

32  220 

2 720 

750 

46  300 1 

9 210 

7 820 

40 

1035 

Yellow  silt  loam 

20  900 

1 880 

720 

58  300 

12  380 

6 270 

30 

1064 

Yellow-gray  sandy  loam . 

18  000 

1 720 

800 

34  280 

5 480 

7 220 

20 

1064.4 

Yellow-gray  sandy  loam 

on  gravel  

20  660 

1 520 

920 

34  580 ( 

5 080 

10  460 

40 

1281 

Dune  sand  

26  000 

1 860 

780 

23  960 

4 920 

8 760 

12  720 

140 

1U90 

Gravelly  loam  

33  580 

2 760 

1 000 

30  920 

11  960 

16  000 

Terrace  Soils 


1527 

Brown  silt  loam  over 

gravel  

62  340 

5 180 

1 340 

36  340 

7 460 

8 900 

60 

1564.4 

Yellow-gray  sandy  loam 

on  gravel  

30  820 

2 680 

1 120 

38  600 

7 480 

9 540 

40 

1560.4 

Brown  sandy  loam  on 

gravel  

28  280 

2 420 

780 

37  660 

7 680 

10  680 

20 

1590.4 

Gravelly  loam  on  gravel 

37  380 

3 240 

1 420 | 33  380 

8 960 

9 160 

1 020 

Swamp  and  Bottom-Land  Soils 


1401 

Deep  peat  (slightly  de- 

composed moss)  

445  080 

7 990 

670 

6 120 

3 360 

2 850 

8 380 

1401 

Deep  peat,  normal  phase 

398  040 

32  570 

1 540 

3 900 

6 260 

24  970 

140 

1402 

Medium  peat  on  clay . . . 

206  230 

17  380 

1 240 

16  450 

9 140 

18  450 

50 

1402.2 

Medium  peat  on  sand . . . 

271.560 

18  450 

1 080 

12  420 

8 080 

18  860 

80 

1403 

Shallow  peat  on  clay. . . 

380  800 

27  420 

1 110 

6 410 

6 310 

28  780 

290 

1410 

Peaty  loam  

334  170 

31  650 

2 300 

18  540 

13  410 

40  050 

Often 

1450 

Black  mixed  loam 

164  480 

13  640 

1 740 

35  000 

14  140 

24  760 

16  080 

1454 

Mixed  loam  (bottom 

land)  

89  440 

8 190 

1 490 

34  690 

45  460 

91  180 

301  130 

1482 

Beach  sand  

5 420 

420 

660 

16  100 

9 620 

14  320 

20 

6 


Soil  Report  No.  9 


[April, 


The  variation  among  the  different  types  of  soil  in  Lake  county  with  respect 
to  their  content  of  important  plant-food  elements  is  also  very  marked.  Thus 
the  yellow  silt  loam  contains  in  2 million  pounds  of  surface  soil  sufficient  total 
nitrogen  for  12  “maximum”  crops  of  corn,  sufficient  phosphorus  for  31  crops, 
and  potassium  for  800  such  crops ; while  the  deep  peat  contains  in  1 million 
pounds  of  surface  soil,  nitrogen  for  217,  phosphorus  for  67,  and  potassium  for 
only  53  corn  crops  of  100  bushels  each.  Each  of  these  soil  types  covers  about 
8 percent  of  the  county.  More  than  90  percent  of  the  soils  of  the  county  contain 
no  limestone  in  the  surface  or  subsurface  to  a depth  of  20  inches,  altlio  the  pres- 
ence of  limestone  is  beneficial  for  most  crops,  especially  for  the  valuable  biennial 
and  perennial  legumes,  such  as  the  clovers  and  alfalfa. 

With  an  inexhaustible  supply  of  nitrogen  in  the  air,  and  with  46,000  pounds 
of  potassium  in  the  most  common  timber  soil,  the  economic  loss  in  farming  such 
land  with  some  acidity  and  with  only  750  pounds  of  total  phosphorus  in  the 
plowed  soil  can  be  appreciated  only  by  the  man  who  fully  realizes  that  in  less 
than  one  generation  the  crop  yields  could  be  doubled  by  the  proper  use  of  lime- 
stone and  phosphorus  in  rational  farm  systems,  without  change  of  seed  or  sea- 
son and  with  very  little  more  work  than  is  now  devoted  to  the  fields.  For- 
tunately, some  definite  field  experiments  have  already  been  conducted  on  this 
most  extensive  type  of  soil  in  Lake  county. 

Results  of  Experiments  on  Antioch  Field 

Table  3 shows  in  detail  thirteen  years’  results  secured  from  the  Antioch 
soil  experiment  field  located  on  the  farm  of  Mr.  D.  M.  White,  on  the  yellow-gray 
silt  loam  of  the  late  Wisconsin  glaciation.  Table  4 is  a financial  summary  of 
these  results. 

The  Antioch  field  was  started  in  order  to  learn  as  quickly  as  possible  what 
effect  would  be  produced  by  the  addition  to  this  type  of  soil,  of  nitrogen,  phos- 
phorus, and  potassium,  singly  and  in  combination.  These  elements  were  all 
added  in  commercial  form  until  1911,  after  which  the  use  of  commercial  nitrogen 
was  discontinued  and  crop  residues  were  substituted  in  its  place.  (See  report  of 
Urbana  field  for  further  explanations,  page  9.)  Only  a small  amount  of  lime 
was  applied  at  the  beginning,  in  harmony  with  the  teaching  which  was  common 
at  that  time;  furthermore,  Plot  101  proved  to  be  abnormal,  so  that  no  conclu- 
sions can  be  drawn  regarding  the  effect  of  lime.  In  order  to  ascertain  the  effect 
produced  by  additions  of  the  different  elements  singly,  Plot  102  must  be  re- 
garded as  the  check  plot.  Three  other  comparisons  are  also  possible  to  deter- 
mine the  effect  of  each  element  under  different  conditions. 

As  an  average  of  40  tests  (4  each  year  for  ten  years),  liberal  applications 
of  commercial  nitrogen  produced  a slight  decrease  in  crop  values;  but  as  an 
average  of  thirteen  years  each  dollar  invested  in  phosphorus  paid  back  $2.54 
(Plot  104),  while  potassium  applied  in  addition  to  phosphorus  (Plot  108)  pro- 
duced no  increase,  the  crops  being  valued  at  the  lower  prices  used  in  the  tabular 
statement.  Thus,  while  the  detailed  data  show  great  variation,  owing  both  to 
some  irregularity  of  soil  and  to  some  very  abnormal  seasons,  with  three  almost 
complete  crop  failures  (1904,  1907,  and  1910),  yet  the  general  summary  strongly 
confirms  the  analytical  data  in  showing  the  need  of  applying  phosphorus  and 


Table  3. — Crop  Yields  in  Soil 


1915 ] 


Lake  County 


7 


!|33' 


6.9 

31.6 

1.3 

2.2 

22.5 

-15.0 

-14.2 

12.8 

-4.2 

-.4 

26.6 

7.2 

CO  CO  CO  00  CO  O 

7”^  7 

333§§  i 

-1.3 

9.3 

.9 

-21.8 

-11.2 

2.S 

. -3.1 
3.9 

3.4 

7.5 

14.5 

10.5 

3S52S  3 

= 33|?  3 

1 -10.0 
-.3 
-3.1 
3.4 
13.1 

1 16.0 

25253  5 

HH  CM 

1.2 

5.0 

3.1 

6.5 
10.3 

4.6 

I Fl,  fin  Ph 


ill 


3No  seed  produced:  clover  plowed 


Soil  Report  No.  9 


[April, 


the  profit  from  its  use,  and  the  loss  in  adding  potassium.  In  most  cases  com- 
mercial nitrogen  damaged  the  small  grains  by  causing  the  crop  to  lodge ; but  in 
those  years  when  a corn  yield  of  40  bushels  or  more  was  secured  by  the  appli- 
cation of  phosphorus  either  alone  or  with  potassium,  then  the  addition  of  nitro- 
gen produced  an  increase. 


Table  4. — Value  op  Crops  per  Acre  in  Thirteen  Years,  Antioch  Field 


Plot 

Soil  treatment  applied 

Total  value  of 
thirteen  crops 

Lower 

prices' 

Higher 

prices2 

101 

None  

$135.12 

$193.03 

171.06 

102 

119.74 

103 

Lime,  nitrogen 

124.70 

178.15 

104 

Lime,  phosphorus  

202.20 

288.85 

105 

Lime,  potassium 

138.88 

198.40 

106 

Lime,  nitrogen,  phosphorus 

179.41 

256.31 

107 

Lime,  nitrogen,  potassium 

133.54 

190.77 

108 

Nitrogen,  phosphorus,  potassium 

201.35 

287.65 

109 

Lime,  nitrogen,  phosphorus,  potassium 

191.22 

273.18 

110 

Nitrogen,  phosphorus,  potassium 

181.18 

258.83 

Value  of  Increase  per  Acre  in  Thirteen  Years 

For  nitrogen ! 

For  phosphorus 

For  nitrogen  and  phosphorus  over  phosphorus 

For  phosphorus  and  nitrogen  over  nitrogen 

For  potassium,  nitrogen,  and  phosphorus  over  nitrogen  and  phosphorus . . . 

$ 4.96 
82.46 
-22.79 
54.71 
11.81 

$ 7.09 
117.79 
-32.54 
78.16 
16.87 

'Wheat  at  70  cents  a bushel,  corn  at  35  cents,  oats  at  28  cents,  hay  at  $7  a ton. 
“Wheat  at  $1  a bushel,  corn  at  50  cents,  oats  at  40  cents,  hay  at  $10  a ton. 


Plate  1. — Clover  in  1913  on  Antioch  Field 
Lime  Applied  and  Residues  Plowed  Under 


1915] 


Lake  County 


9 


From  a comparison  of  the  results  from  the  Urbana,  Sibley,  and  Blooming- 
ton fields  (see  following  pages),  we  must  conclude  that  better  yields  are  to  be 
secured  by  providing  nitrogen  by  means  of  farm  manure  or  legume  crops  grown 
in  the  rotation  than  by  the  use  of  commercial  nitrogen,  which  is  evidently  too 
readily  available,  causing  too  rapid  growth  and  consequent  weakness  of  straw; 
and  of  course  the  atmosphere  is  the  most  economic  source  of  nitrogen  where  that 
element  is  needed  for  soil  improvement  in  general  farming.  (See  Appendix  for 
detailed  discussion  of  “Permanent  Soil  Improvement.” 


Results  of  Field  Experiments  at  Urbana 

No  soil  experiment  field  has  been  conducted  on  the  brown  silt  loam  of  the 
late  Wisconsin  glaciation,  but  we  may  well  consider  the  results  from  long-con- 
tinued experiments  on  similar  soil  in  the  early  Wisconsin  glaciation,  as  at  Urbana 
in  Champaign  county,  at  Sibley  in  Ford  county,  and  at  Bloomington  in  McLean 
county.  (Long-cultivated  fields  of  brown  silt  loam  in  the  late  Wisconsin  gla- 
ciation are  sometimes  found  to  contain  no  more  phosphorus  or  nitrogen  than  the 
average  in  the  brown  silt  loam  of  the  early  Wisconsin.) 

A three-year  rotation  of  corn,  oats,  and  clover  was  begun  on  the  North  Farm 
at  the  University  of  Illinois  in  1902,  on  three  fields  of  typical  brown  silt  loam 
prairie  land  which,  after  twenty  years  or  more  of  pasturing,  had  grown  corn  in 
1895,  1896,  and  1897  (when  careful  records  were  kept  of  the  yields  produced), 
and  had  then  been  cropped  with  clover  and  grass  on  one  field  (Series  100),  oats 
on  another  (Series  200),  and  oats,  cowpeas,  and  corn  on  the  third  field  (Series 
300)  until  1901. 


Plate  2. — Clover  in  1913  on  Antioch  Field 
Lime  and  Phosphorus  Applied 


10 


Soil  Bepobt  No.  9 


[April, 


From  1902  to  1910  the  three-year  rotation  (with  cowpeas  in  place  of  clover 
in  1902)  was  followed ; the  average  yields  are  recorded  in  Table  5.  A small  crop 
of  cowpeas  in  1902  and  a partial  crop  of  clover  in  1904  constituted  all  the  hay 
harvested  during  the  first  rotation,  mammoth  clover  grown  in  1903  having  lodged 
so  that  it  was  plowed  under.  (The  yields  were  taken  by  carefully  weighing  the 
clover  from  small  representative  areas,  but  while  the  differences  were  thus  ascer- 
tained and  properly  credited  temporarily  to  the  different  soil  treatments,  they 
must  ultimately  reappear  in  subsequent  crop  yields,  and  consequently  the  1903 
clover  crop  is  omitted  from  Table  5 in  computing  yields  and  values. ) The  aver- 
age yields. given  represent  one-third  of  the  two  small  crops. 

From  1902  to  1907  legume  cover  crops  (Le),  such  as  cowpeas  and  clover, 
were  seeded  in  the  corn  at  the  last  cultivation  on  Plots  2,  4,  6,  and  8,  but  the 
growth  was  small  and  the  effect,  if  any,' was  to  decrease  the  returns  from  the 
regular  crops.  Since  1907  crop  residues  (R)  have  been  returned  to  those  plots. 
These  consist  of  the  stalks  of  corn,  the  straw  of  small  grains,  and  all  legumes 
except  alfalfa  hay  and  the  seed  of  clover  and  soybeans. 

On  Plots  3,  5,  7,  and  9,  manure  (M)  was  applied  for  corn  at  the  rate  of 
0 tons  per  acre  during  the  second  rotation,  and  subsequently  as  many  tons  of 
manure  have  been  applied  as  there  were  tons  of  air-dry  produce  harvested  from 
the  corresponding  plots. 

Lime  (L)  was  applied  on  Plots  4 to  10  at  the  rate  per  acre  of  250  pounds 
of  air-slaked  lime  in  1902  and  600  pounds  of  limestone  in  1903.  Subsequently 
2 tons  per  acre  of  limestone  was  applied  to  these  plots  on  Series  100  in  1911,  on 
Series  200  in  1912,  on  Series  300  in  1913,  and  on  Series  400  in  1914 ; also  2^2 
tons  per  acre  on  Series  500  in  1911,  two  more  fields  having  been  brought  into 
rotation,  as  explained  below. 

Phosphorus  (P)  has  been  applied  on  Plots  6 to  9 at  the  rate  of  25  pounds  per 
acre  per  annum  in  200  pounds  of  steamed  bone  meal ; but  beginning  with  1908, 
one  half  of  each  phosphorus  plot  has  received  600  pounds  of  rock  phosphate  in 
place  of  the  200  pounds  of  bone  meal,  the  usual  practice  being  to  apply  and  plow 
under  at  one  time  all  phosphorus  and  potassium  required  for  the  rotation. 

Potassium  (K=kalium)  has  been  applied  on  Plots  8 and  9 at  the  yearly 
rate  of  42  pounds  per  acre  in  100  pounds  of  potassium  sulfate,  regularly  in  con- 
nection with  the  bone  meal  and  rock  phosphate. 

On  Plot  10  about  five  times  as  much  manure  and  phosphorus  are  applied 
as  on  the  other  plots,  but  this  “extra  heavy”  treatment  was  not  begun  until 
1906,  only  the  usual  lime,  phosphorus,  and  potassium  having  been  applied  in 
previous  years.  The  purpose  in  making  these  heavy  applications  is  to  try  to 
determine  the  climatic  possibilities  in  crop  yields  by  removing  the  limitations 
of  inadequate  fertility. 

Series  400  and  500  were  cropped  in  corn  and  oats  from  1902  to  1910,  but 
the  corresponding  plots  were  treated  the  same  as  in  the  three-year  rotation. 
Beginning  with  1911',  the  five  series  have  been  used  for  a combination  rotation, 
wheat,  corn,  oats,  and  clover  being  rotated  for  five  years  on  four  fields,  while 
alfalfa  occupies  the  fifth  field,  which  is  then  to  be  brought  under  the  four-crop 
system  to  make  place  for  alfalfa  on  one  of  the  other  fields  for  another  five-year 
period,  and  so  on.  (See  Table  6.) 


1916] 


Lake  County 


2 3 

<4  V 
ca  ■< 
os  J 


5 o 

§ ” 

g 3 

If 

ii 

S3 


S m 
a z 
^ £ 
I S 

wffl 


of  3 
>ps 

Higher 

prices 

$64.02 

62.41 

78.43 

67.53 

85.85 

90.10 

107.16 

84.65 

105.89 

100.27 

1 Value 
er< 

Lower 

prices 

$44.81 

43.69 

54.90 

47.27 

60.09 

63.07 

75.01 

59.26 

74.12 

70.19 

£ g? 

O Ofl 
O 

O CO  CO  Cl  ^ 
co  os  to  0 os 
CM*  rH*  CM*  CM*  M* 

(2.64) 

4.17 

(1.99) 

3.90 

3.79 

Oats, 

bu. 

00  rH  CQ  t>  LO  I LO  -rjj  LO  CO  CO 
0 cb  cb  to  rfi  lo  cb  co*  hh 

HHHtHtTjHHHjLOLOLOLOLO 

Corn, 

bu. 

49.4 

51.5 

69.3 
58.1 

74.9 
~83.8" 

86.6 
86.7 

90.9 

81.3 

Soil 

treat- 

ment 

0 

R 

M 

RL.... 
ML. . . . 
RLP . . . 
MLP. . . 
RLPK 
MLPK 
MxLPx 

<35  lO  b-  05  <M  I -JO  ■<(<  < 

o co  o co  <35  ,eo  cs  < 
in  co’  os'  o o’  <35’  < 

NNX^Oipo< 


CD  CD  N O I 


to  co  qo  to  co  Icq  os  < 

CM*  rH  00*  IO  co  © CO*  ' 
IO  IO  IO  IO  CD  N l>  1 


O o 

5 


OS  S CD  CO  CD 


CO  O O0  CD  GO 
CO  CQ  tJH  00  OS* 
^ IQ  IO  IO  LO 


s cd  r>  os  os 

© rH  rH  CO  M* 

t>-  t-  fr-  to  CO 


LO  LO  CO  00 
i 06  © ci  ^ 
CDOOSOO 


I GQ  00  CO  rH 
> CO*  CO*  LO*  © 
) OS  OS  OS  OS 


P Pn  P d Pm  ^ 

Pd 


I rH  rH  os  CO  © 
<M*  rH  rH  <M*  00 
CO  CO  CO  CO  CO 


:00  O CO  CM  CO  O OS  CO  CO  00 

| 'H  00  CO  CO  CO  C l>  LO  W t- 

I CO*  <M*  CO*  CO  t>-  OS  CO  OS  CO  CO 


: U 

O * 01 

A u 


^v;i 

hJ5T. 


•£  O 0 


...  <15 


II  o 
Pu  -g 


'I  ' ' 


; 00  H LO  IO 
6 00  © © cb 

0 00  OS  OS  00 


LO  CO  N 00  OS  O 


§ a 
sis 


3S 


12 


Soil  Report  No.  9 


[ April, 


Table  6.— Yields  per  Acre,  Four-year  Averages,  1911-1914:  Urbana  Field 
Brown  Silt  Loam  Prairie;  Early  Wisconsin  Glaciation 


Serial 

plot 

No. 

Soil 

treat- 

ment 

Wheat, 

bu. 

Corn, 

bu. 

Oats, 

bu. 

Soybeans-3, 
tons  (bu.) 

Clover-1,  *| 
tons  (bu.) 

Alfalfa, 

tons 

Value  of  5 crops 

Lower 

prices 

Higher 

prices 

' 1“ 

0.  .77777. 

18.3 

50.8 

39.8 

L60 

1.70 

L70~ 

~$65W 

$92.87 

2 

R 

19.7 

53.8 

40.6 

(20.1) 

( -74) 

1.27 

64.72 

92.47 

3 

M 

20.3 

59.3 

48.8 

1.60 

1.43 

1.13 

67.44 

96.35 

4 

RL 

22.3 

55.7 

42,8 

(19.0) 

(1.03) 

1.19 

67.20 

96.00 

5 

ML 

24.9 

58.6 

51.6 

1.66 

1.67 

76.19 

108.S4 

6~ 

RLP .... 

37.4 

62.2 

58.7 

(2L0) 

(2.48)  _ 

—fUjST 

98.58 

140.83" 

7 

MLP 

36.6 

63.8 

60.9 

1.88 

2.90 

2.63 

98.36 

140.51 

8 

RLPK. . . 

36.1 

58.9 

59.1 

(22.2) 

(1.41) 

2.58 

94.61 

135.16 

9 

MLPK . . 

35.3 

59.6 

65.1 

2.09 

2.72 

2.66 

98.15 

140.22 

10 

MxLPx.  . 

43.5  | 

55.7 

67.2 

2.14 

2.94 

I 2.84 

105.02 

150.03 

From  1911  'to  1914  soybeans  were  substituted  three  years  because  of  clover 
failure,  and  three-fourths  of  the  soybeans  and  one-fourth  of  the  clover  are  used 
to  compute  values.  Alfalfa  from  the  1911  seeding  so  nearly  failed  that  after 
cutting  one  crop  in  1912,  the  field  was  plowed  and  reseeded.  The  average  yield 
reported  for  alfalfa  in  Table  6 is  one-fourth  of  the  combined  crops  of  1912,  1913, 
and  1914. 


Plate  3. — Clover  in  1913  on  Urbana  Field 
Farm  Manure  Applied 
Yield,  1.43  Tons  per  Acre 


191S\ 


Lake  County 


13 


The  “higher  prices”  allowed  for  produce  are  $1  a bushel  for  wheat  and 
soybeans,  50  cents  for  corn,  40  cents  for  oats,  $10  for  clover  seed,  and  $10  a ton 
for  hay;  while  the  “lower  prices”  are  70  percent  of  these  values,  or  70  cents 
for  wheat  and  soybeans,  35  cents  for  corn,  28  cents  for  oats,  $7  for  clover  seed, 
and  $7  a ton  for  hay.  The  double  set  of  values  is  used  to  emphasize  the  fact 
that  a given  practice  may  or  may  not  be  profitable,  depending  upon  the  prices 
of  farm  produce.  The  lower  prices  are  conservative,  and  unless  otherwise  stated, 
they  are  the  values  regularly  used  in  the  discussion  of  results.  It  should  be 
understood  that  the  increase  produced  by  manures  and  fertilizers  requires  in- 
creased expense  for  binding  twine,  shocking,  stacking,  baling,  threshing,  haul- 
ing, storing,  and  marketing.  Measured  by  the  average  Illinois  prices  for  the 
past  ten  years,  these  lower  values  are  high  enough  for  farm  crops  standing  in 
the  field  ready  for  the  harvest. 

The  cost  of  limestone  delivered  at  the  farmers’  railroad  station  in  carload 
lots  averages  about  $1.25  per  ton.  Steamed  bone  meal  in  carloads  costs  from 
$25  to  $30  per  ton.  Fine-ground  raw  rock  phosphate  containing  from  260  to 
280  pounds  of  phosphorus,  or  as  much  as  the  bone  meal  contains,  ton  for  ton, 
but  in  less  readily  available  form,  usually  costs  the  farmer  from  $6.50  to  $7.50  per 
ton  in  carloads.  (Acid  phosphate  carrying  half  as  much  phosphorus,  but  in 
soluble  form,  commonly  costs  from  $15  to  $17  per  ton  delivered  in  carload  lots 


Plate  4. — Clover  in  1913  on  Urbana  Field 
Farm  Manure,  Limestone,  and  Phosphorus  Applied 
Yield,  2.90  Tons  per  Acre 


14 


Soil  Report  No.  9 


[April, 


in  central  Illinois.)  Under  normal  conditions  potassium  costs  about  6 cents  a 
pound,  or  $2.50  per  acre  per  annum  for  the  amount  applied  in  these  experi- 
ments, the  same  as  the  cost  of  200  pounds  of  steamed  bone  meal  at  $25  per  ton. 

To  these  cash  investments  must  be  added  the  expense  of  hauling  and  spread- 
ing the  materials.  This  will  vary  with  the  distance  from  the  farm  to  the  rail- 
road station,  with  the  character  of  roads,  and  with  the  farm  force  and  the  imme- 
diate requirements  of  other  lines  of  farm  work.  It  is  the  part  of  wisdom  to  order 
such  materials  in  advance  to  be  shipped  when  specified,  so  that  they  may  be  re- 
ceived and  applied  when  other  farm  work  is  not  too  pressing  and,  if  possible, 
when  the  roads  are  likely  to  be  in  good  condition. 

The  practice  of  seeding  legume  cover  crops  in  the  cornfield  at  the  last  culti- 
vation where  oats  are  to  follow  the  next  year  has  not  been  found  profitable,  as  a 
rule,  on  good  corn-belt  soil ; but  the  returning  of  the  crop  residues  to  the  land 
may  maintain  the  nitrogen  and  organic  matter  equally  as  well  as  the  hauling  and 
spreading  of  farm  manure, — and  this  makes  possible  permanent  systems  of  farm- 
ing on  grain  farms  as  well  as  on  live-stock  farms,  provided,  of  course,  that  other 
essentials  are  supplied.  (Clover  with  oats  or  wheat,  as  a cover  crop  to  be  plowed 
under  for  corn,  often  gives  good  results.) 

At  the  lower  prices  for  produce,  manure  (6  tons  per  acre)  was  worth  $1.05 
a ton  as  an  average  for  the  first  three  years  it  was  applied  (1905  to  1907).  The 
next  rotation  the  average  application  of  10.21  tons  per  acre  on  Plot  3 was  worth 
$10.09,  or  99  cents  a ton.  The  last  four  years,  1911  to  1914,  the  average  amount 
applied  (once  for  the  rotation)  on  Plot  3 was  11.35  tons  per  acre,  worth  $6.42, 
or  57  cents  a ton,  as  measured  by  its  effect  on  the  wheat,  corn,  oats,  soybeans, 
and  clover.  Thus,  as  an  average  of  the  ten  years’  results,  the  farm  manure  ap- 
plied to  Plot  3 has  been  worth  84  cents  a ton  on  common  corn-belt  prairie  soil, 
with  a good  crop  rotation  including  legumes.  During  the  last  rotation  period 
moisture  has  been  the  limiting  factor  to  such  an  extent  as  probably  to  lessen  the 
effect  of  the  manure. 

Aside  from  the  crop  residues  and  manure,  each  addition  affords  a duplicate 
test  as  to  its  effect.  Thus  the  effect  of  limestone  is  ascertained  by  comparing  Plots 
4 and  5,  not  with  Plot  1,  but  with  Plots  2 and  3 ; and  the  effect  of  phosphorus  is 
ascertained  by  comparing  Plots  6 and  7 with  Plots  4 and  5,  respectively. 

As  a general  average  the  plots  receiving  limestone  have  produced  $1.22  an 
acre  a year  more  than  those  without  limestone,  and  this  corresponds  to  more  than 
$6  a ton  for  all  of  the  limestone  applied;  but  the  amounts  used  before  1911 
were  so  small  and  the  results  vary  so  greatly  with  the  different  plots,  crops,  and 
seasons  that  final  conclusions  cannot  be  drawn  until  further  data  are  secured, 
the  first  2-ton  applications  having  been  completed  only  for  1914.  However,  all 
comparisons  by  rotation  periods  show  some  increase  for  limestone,  varying  from 
82  cents  on  three  acres  (Plot  4)  during  the  first  rotation,  to  $8.75  on  five  acres 
(Plot  5)  as  an  average  of  the  last  four  years;  and  the  need  of  limestone  for  best 
results  and  highest  profits  seems  well  established. 

As  an  average  of  duplicate  trials  (Plots  6 and  7),  phosphorus  in  bone  meal 
produced  increases  valued  at  $1.92  per  acre  per  annum  for  the  first  three  years 
and  at  $4.67  for  the  next  three;  and  the  corresponding  subsequent  average  in- 
creases from  bone  meal  and  raw  phosphate  (one-half  plot  of  each)  were  $5.12  for 
the  third  rotation  and  $5.36  for  the  last  four  years,  1911  to  1914.  The  annual 


Lake  County 


15 


1915 ] 

expense  per  acre  for  phosphorus  is  $2.80  in  bone  meal  at  $28  a ton,  or  $2.10  for 
rock  phosphate  at  $7  a ton. 

Potassium,  applied  at  an  estimated  cost  of  $2.50  an  acre  a year,  seemed  to 
produce  slight  increases,  as  an  average,  during  the  first  and  second  rotations; 
but  subsequently  those  increases  have  been  slightly  more  than  lost  in  reduced 
average  yields,  the  net  result  to  date  being  an  average  loss  of  $2.53  per  acre 
per  annum,  including  the  cost  of  the  potassium. 

Thus  phosphorus  nearly  paid  its  cost  during  the  first  rotation,  and  has  sub- 
sequently paid  its  annual  cost  and  about  100  percent  net  profit ; while  potassium, 
as  a general  average,  has  produced  no  effect,  and  money  spent  for  its  applica- 
tion has  been  lost.  These  field  results  are  in  harmony  with  what  might  well  be 
expected  on  land  naturally  containing  in  the  plowed  soil  of  an  acre  only  about 
1,200  pounds  of  phosphorus  and  more  than  36,000  pounds  of  potassium. 

The  total  value  of  five  average  crops  harvested  from  the  untreated  land  dur- 
ing the  last  four  years  is  $65.  Where  limestone  and  phosphorus  have  been  used 
together  with  organic  manures  (either  crop  residues  or  farm  manure),  the  cor- 
responding value  exceeds  $98.  Thus  200  acres  of  the  properly  treated  land 
would  produce  as  much  in  crops  and  in  value  as  300  acres  of  the  untreated  land. 

The  excessive  applications-  on  Plot  10  have  usually  produced  rank  growth 
of  straw  and  stalk  with  the  result  that  oats  have  often  lodged  badly  and  corn 
has  frequently  suffered  from  drouth  and  eared  poorly.  Wheat,  however,  has 
as  an  average  yielded  best  on  this  plot.  The  largest  yield  of  corn  on  Plot  10  was 
118  bushels  per  acre  in  1907. 

Results  of  Experiments  of  Sibley  Field 

Table  7 gives  the  results  obtained  during  twelve  years  from  the  Sibley  soil 
experiment  field  located  in  Ford  county  on  the  typical  brown  silt  loam  prairie 
of  the  Illinois  corn  belt. 

Previous  to  1902  this  land  had  been  cropped  with  corn  and  oats  for  many 
years  under  a system  of  tenant  farming,  and  the  soil  had  become  somewhat  defi- 
cient in  active  organic  matter.  While  phosphorus  was  the  limiting  element  of 
plant  food,  the  supply  of  nitrogen  becoming  available  annually  was  but  little  in 
excess  of  the  phosphorus,  as  is  well  shown  by  the  corn  yields  for  1903,  when  the 
addition  of  phosphorus  produced  an  increase  of  8 bushels,  nitrogen  produced 
no  increase,  but  nitrogen  and  phosphorus  together  increased  the  yield  by  15 
bushels. 

After  six  years  of  additional  cropping,  however,  nitrogen  appeared  to  be- 
come the  most  limiting  element,  the  increase  in  the  corn  in  1907  being  9 bushels 
from  nitrogen  and  only  5 bushels  from  phosphorus,  while  both  together  pro- 
duced an  increase  of  33  bushels.  By  comparing  the  corn  yields  for  the  four 
years  1902,  1903,  1906,  and  1907,  it  will  be  seen  that  the  untreated  land  appar- 
ently grew  less  productive,  whereas,  on  land  receiving  both  phosphorus  and 
nitrogen,  the  yield  appreciably  increased,  so  that  in  1907,  when  the  untreated 
rotated  land  produced  only  34  bushels  of  corn  per  acre,  a yield  of  72  bushels 
(more  than  twice  as  much)  was  produced  where  lime,  nitrogen,  and  phosphorus 
had  been  applied,  altho  the  two  plots  produced  exactly  the  same  yield  (57.3 
bushels)  in  1902. 


16 


Soil  Report  No.  9 


[April, 


Even  in  the  unfavorable  season  of  1910  the  yield  of  the  highest  producing 
plot  exceeded  the  yield  of  the  same  plot  in  1902,  while  the  untreated  land  pro- 
duced less  than  half  as  much  as  it  produced  in  1902.  The  prolonged  drouth  of 
1911  resulted  in  almost  a failure  of  the  corn  crop,  but  nevertheless  the  effect  of 
soil  treatment  was  seen.  Phosphorus  appeared  to  be  the  first  limiting  element 
again  in  1909,  1910,  and  1911;  while  the  lodging  of  oats,  especially  on  the  nitro- 
gen plots,  in  the  exceptionally  favorable  season  of  1912,  produced  very  irregular 
results.  In  1913,  wheat  averaged  6.6  bushels  without  nitrogen  or  phosphorus 


Table  7. — Crop  Yields  in  Soil  Experiments,  Sibley  Field 


Brown  silt  loam  prairie ; 1 
early  Wisconsin 
glaciation 

Corn  Corn  Oats  Wheat 
1902,19031904  1905 

ill 

Corn 

1906 

Corn 

1907 

Oats  j Wheat)  Corn  [ 
1908  1909  1910| 

Corn 

1911 

Oats 

1912 

Wheat 

1913 

Plot 

Soil  treatment 
applied 

Bushels  per 

acre 

101 

None  

57.3 

50.4 

74.4 

29.5 

36.7 

33.9 

25.9 

25.3 

26.6 

20.71 

84.4 

5.5 

102 

Lime  

GO.O 

54.0 

74.7 

31.7 

39.2 

38.9 

24.7 

28.8 

34.0 

22.2 

85.6 

6.8 

T03" 

Lime,  nitro 

60.0 

54.3 

77.5 

32JT 

4L7 

18J 

36.3 

19.0 

2976 

“22 A 

\~253 

18.3 

104 

Lime,  phos 

61.3 

62.3 

92.5 

36.3 

44.8 

43.5 

25.6 

32.2 

52.0 

31.6 

92.3 

10.7 

105 

Lime,  potas 

56.0 

49.9 

74.4 

30.2 

37.5 

34.9 

22.2 

23.2 

34.2 

21.6 

83.1 

7.5 

10G 

Lime,  nitro.,  phos..  . 

57.3 

69.1 

88.4 

45  2 

68.5 

72^3 

45.6 

33.3 

~5iL6 

"3^3 

42.2 

24.7 

107 

Lime,  nitro.,  potas.. 

53.3 

51.4 

75.9 

37.7 

39.7 

51.1 

42.2 

25.8 

46.2 

20.1 

55.6 

19.2 

108 

Lime,  phos.,  potas.. . 

58.7 

60.9 

80.0 

39.8 

41.5 

39.8 

27.2 

28.5 

43.0 

31.8 

79.7 

11.8 

109 

Lime,  nitro.,  phos., 
potas 

58.7 

65.9 

82.5 

48.0 

69.5 

80.1 

52.8 

35.0 

58.0 

35.7 

57.2 

24.5 

110 

Nitro.,  phos.,  potas.. 

60.0 

60.1 

I 85.0 

48.5 

63.3 

72.3 

44.1 

30.8 

64.4 

31.5 

54.1 

18.0 

Increase:  Bushels  per  Acre 


For  nitrogen 

.0 

.3 

2.8 

1.1 

2.5 1 9.2 

11.6 

-9.8 

-5.01  .2 

-60.3 

11.5 

For  phosphorus  

1.3 

8.3 

17.8 

4.6 

5.6  4.6 

.9 

3.4 

18.0 1 9.4 

0.7 

3.9 

For  potassium  

-4.0 

-4.1 

-.3 

-1.5 

-1.7,  -4.0 ! 

-2.5 

-5.6 

.2,  -.6 

-2.5 

.7 

For  nitro.,  phos.  over 
phos 

-4.0 

6.8 

-4.1 

8.9 

1 

23.7,  28.8 

20.0 

1.1 

1 

3.6  3.7 

-50.1 

14.0 

For  phos.,  nitro.  over 
nitro  

-2.7 

14.8 

10.9 

12.4 

1 

24.8  24.2 1 

9.3 

14.3 

1 

26.6  12.9 

16.9 

6.4 

For  potas.,  nitro.,  phos. 
over  nitro.,  phos 

1.4' 

-3.2 

-5.9 

2.8 

1.0  7.8' 

7.2 

1.7 

1 

2.4  .4 

15.0 

-.2 

Value  of  Crops  per  Acre  in  Twelve  Years 


Plot 

Soil  treatment  applied 

Total  \ 
twelve 
Lower 
prices 

'alue  of 
, crops 
Higher 
prices 

101 

$172.89 

186.51 

$246.98 

266.45 

102 

103 

Lime,  nitrogen 

177.44 

253.49 

104 

Lime,  phosphorus 

217.78 

311.11 

105 

Lime,  potassium 

167.32 

239.03 

106 

Lime,  nitrogen,  phosphorus 

246.91 

352.73 

107 

Lime,  nitrogen,  potassium 

198.16 

283.08 

108 

Lime,  phosphorus,  potassium 

204.90 

292.71 

"loa 

Lime,  nitrogen,  phosphorus,  potassium 

257.91 

368.45 

110 

Nitrogen,  phosphorus,  potassium 

242.47 

346.38 

Value  of  Increase  per  Acre  in  Twelve  Years 

For  nitrogen 

$ 9.07 

$12.96 

For  phosphorus 

For  nitrogen  and  phosphorus  over  phosphorus 

31.27 

29.13 

44.66 

41.62 

For  phosphorus  and  nitrogen  over  nitrogen 

69.47 

99.24 

Fnr  'nni.n.Rsi'ii.nm.  nifrnorpn  ntul  TVhnsTVhnrns  nvpr  nifrnorpn  anrl  TVhnsnhnrns 

11.00 

15.72 

1915] 


Lake  County 


17 


(Plots  101,  102,  105)  and  22.4  bushels  where  both  nitrogen  and  phosphorus  were 
added  (Plots  106,  109,  110). 

In  the  lower  part  of  Table  7 are  shown  the  total  values  per  acre  of  the  twelve 
crops  from  each  of  the  ten  different  plots,  the  amounts  varying  from  $167.32  to 
$257.91,  with  corn  valued  at  35  cents  a bushel,  oats  at  28  cents,  and  wheat  at 
70  cents.  Phosphorus  without  nitrogen  has  produced  $31.27  in  addition  to  the 
increase  by  lime,  but  with  nitrogen  it  has  produced  $69.47  above  the  crop  values 
where  only  lime  and  nitrogen  have  been  used.  The  results  show  that  in  26  cases 
out  of  48  the  addition  of  potassium  has  decreased  the  crop  yields.  Even  when 
applied  in  addition  to  phosphorus,  and  with  no  effort  to  liberate  potassium  from 
the  soil  by  adding  organic  matter,  potassium  has  produced  no  increase  in  crop 
values  as  an  average  of  the  results  from  Plots  108  and  109. 

By  comparing  Plots  101  and  102,  and  also  109  and  110,  it  is  seen  that  lime 
has  produced  an  average  increase  of  $14.53,  or  $1.21  an  acre  a year.  This  in- 
crease on  these  plots  is  practically  the  same  as  at  Urbana,  and  it  suggests  that  the 
time  is  here  when  limestone  must  be  applied  to  some  of  these  brown  silt  loam  soils. 

While  nitrogen,  on  the  whole,  has  produced  an  appreciable  increase,  espe- 
cially on  those  plots  to  which  phosphorus  has  also  been  added,  it  has  cost,  in  com- 
mercial form,  so  much  above  the  value  of  the  increase  produced  that  the  only 
conclusion  to  be  drawn,  if  we  are  to  utilize  this  fact  to  advantage,  is  that  the 
nitrogen  must  be  secured  from  the  air. 

Results  of  Experiments  on  Bloomington  Field 

Space  is  taken  to  insert  Tables  8 and  9,  giving  all  results  thus  far  obtained 
from  the  Bloomington  soil  experiment  field,  which  is  also  located  on  the  brown 
silt  loam  prairie  soil  of  the  Illinois  corn  belt. 

The  general  results  of  the  thirteen  years’  work  on  the  Bloomington  field  tell 
much  the  same  story  as  those  from  the  Sibley  field.  The  rotations  have  differed 
since  1905  by  the  use  of  clover  and  the  discontinuing  of  the  use  of  commercial 
nitrogen  on  the  Bloomington  field, — in  consequence  of  which  phosphorus  without 
commercial  nitrogen,  on  the  Bloomington  field,  has  produced  an  even  larger  in- 
crease ($99.85)  than  has  been  produced  by  phosphorus  and  nitrogen  over  nitro- 
gen on  the  Sibley  field  ($69.47) . 

It  should  be  stated  that  a draw  runs  near  Plot  110  on  the  Bloomington  field, 
that  the  crops  on  that  plot  are  sometimes  damaged  by  overflow  or  imperfect 
drainage,  and  that  Plot  101,  occupies  the  lowest  ground  on  the  opposite  side  of 
the  field.  In  part  because  of  these  irregularities  and  in  part  because  only  one 
small  application  has  been  made,  no  conclusions  can  be  drawn  in  regard  to  lime. 
Otherwise  all  results  reported  in  Table  8 are  considered  reliable.  They  not  only 
furnish  much  information  in  themselves,  but  they  also  offer  instructive  com- 
parison with  the  Sibley  field. 

Wherever  nitrogen  has  been  provided,  either  by  direct  application  or  by  the 
use  of  legume  crops,  the  addition  of  the  element  phosphorus  has  produced  very 
marked  increases,  the  average  yearly  increase  for  the  Bloomington  field  being 
worth  $7.02  an  acre.  This  is  $4.52  above  the  cost  of  the  phosphorus  in  200  pounds 
of  steamed  bone  meal,  the  form  in  which  it  is  applied  on  the  Sibley  and  the 
Bloomington  fields.  On  the  other  hand,  the  use  of  phosphorus  without  nitrogen 


Table  8.- 


Soil  Report  No.  9 


Oats 

1914 

Bushels  or  tons  per  acre 

QO  50  [OO  © °0  |< 
ai  o © io  •£$  i 

oq  ^ CO  00  ji 

62.3 

34.5 

63.1 

54.4 

44.8 

Corn  | Corn 
1912  j 1913  i 

^ o 
o4  © 

CO  CO 

37.5 

44.1 

32.1 

50.4 

34.5 
49.4 

49.0 

33.8 

55.2 

47.9 

62.5 

74.5 
57.8 

86.1 

58.9 

79.2 

83.4 

78.3 

Wheat 

1911 

22.5 

22.5 

25.6 

57.6 

21.7 

60.2 

27.3 

54.0 

60.4 

61.0 

Clover2 

1910 

1.56 

1.09 

QOWN 
’ iH 

5*5 

® 05 

<3§ 

46.4 

53.6 

49.4 

63.8 

45.3 

72.5 
51.1 

59.5 

64.2 

55.3 

fl  oo 
fH  O 
O 05 
O rH 

40.3 

35.3 

36.9 

47.5 

36.2 

45.8 

31.0 

57.2 

58.1 

51.4 

Corn 

1907| 

60.8  I 
63.1 

64.3 

82.1 

64.1 

78.9 

64.3 

81.4 

88.4 

78.0 

Clover 

1906 

05  oo 
CO  io 

.46 

1.65 

.51 

Vs  3 

CC 

Wheat 

1905 

30.8  | 

28.8 

30.5 

39.2 

33.2 

50.9 

29.5 

37.8 

51.9 

51.1 

Oats 

1904 

54.8  1 

60.8 

oo  t>-  iq 
05  CQ  <M* 
a t>  to 

85.3 

66.4 
70.3 

90.5 

71.4 

Corn 

1903 

63.9 

60.3 

in  © 

ci  CO  CD 
IO  10 

77.6 

58.9 

74.8 

80.9 

73.1 

Corn 

1902 

30.8  i 
37.0 

35.1 

41.7 

37.7 

43.9 

40.4 

50.1 

52.7 

52.3 

Brown  silt  loam  prairie; 
early  Wisconsin  glaciation 

Soil  treatment 
applied 

None 

Lime 

Lime,  crop  residues1 

Lime,  phosphorus 

Lime,  potassium 

Lime,  residues,1  phosphorus 

Lime,  residues,1  potassium 

Lime,  phosphorus,  potassium 

Lime,  residues,1  phosphorus,  potassium 

Residues,  phosphorus,  potassium 

Plot 

101 

102 

CO  T*  ID 

o o o 

109 

110 

7.5 

14.1 

2.1 

6.3 

12.9 

-1.4 

© CO  05  CO  CO  t''- 

-4.2 

10.2 

-8.3 

8.7 

23.1 

-8.3 

1.6 

12.2 

.9 

-1.7 

8.9 

12.3 

' 1.2 
19.0 
1.0 
-3.2 
14.6 
9.5 

-.12 

1.07 

-.07 

-1.65 

-.46 

.00 

10.4 
4.4 

11.7 

20.4 
1 1.0 

9.0 

11.9 

1.7 

12.6 

15.5 

5.2 

-.8 

12.7 

-3.9 

4.6 

18.1 

3.3 

^■222 

[April, 


“The  figures  in  parenthses  mean  bushels  of  seed;  the  others,  tons  of  hay. 
“Clover  smothered  by  previous  wheat  crop. 


1015 ] 


Lake  County 


19 


Table  9. — Value  op  Crops  per  Acre  in  Thirteen  Years,  Bloomington  Field 


Plot 

Soil  treatment  applied 

Total  value  of 
thirteen  crops 

Lower 

prices 

Higher 

prices 

101 

102 

“$186.83 

186.76 

$266.90 

266.80 

103 

104 

105 

193.83 

276.90 

Lime,  phosphorus 

Lime,  potassium 

286.61 

190.53 

409.45 

272.19 

106 

Lime,  residues,  phosphorus 

285.03 

407.19 

107 

Lime,  residues,  potassium 

191.10 

273.00 

108 

Lime,  phosphorus,  potassium 

294.91 

421.31 

109 

Lime,  residues,  phosphorus,  potassium 

284.47 

406.39 

110 

Residues,  phosphorus,  potassium 

259.10 

370.15 

Value  of  Increase  per  Acre  in  Thirteen  Years 

For  residues 

For  phosphorus 

1 $ 7.07 
99.85 

$ 10.10 
142.65 

For  residues  and  phosphorus  over  phosphorus 

-1.58 

-2.26 

For  phosphorus  and  residues  over  residues 

91.20 

130.29 

For  potassium,  residues,  and  phosphorus  over  residues  and  phosphorus. . . . 

-.56 

-.80 

will  not  maintain  the  fertility  of  the  soil  (see  Plots  104  and  106,  Sibley  field). 
As  the  only  practical  and  profitable  method  of  supplying  nitrogen,  a liberal  use 
of  clover  or  other  legumes  is  suggested,  the  legume  to  be  plowed  under  either 
directly  or  as  manure,  preferably  in  connection  with  the  phosphorus  applied, 
especially  if  raw  rock  phosphate  is  used. 

Prom  the  soil  of  the  best  treated  plots  on  the  Bloomington  field,  180  pounds 
per  acre  of  phosphorus,  as  an  average,  has  been  removed  in  the  thirteen  crops. 
This  is  equal  to  15  percent  of  the  total  phosphorus  contained  in  the  surface  soil 
of  an  acre  of  the  untreated  land.  In  other  words,  if  such  crops  could  be  grown 


Plate  5. — Corn  in  1912  on  Bloomington  Field 
On  Left,  Residues,  Lime,  and  Potassium:  Yield,  58.9  Bushels 
On  Right,  Residues,  Lime,  and  Phosphorus:  Yield,  86.1  Bushels 


20 


Soil  Report  No.  9 


[April, 


for  eighty  years,  they  would  require  as  much  phosphorus  as  the  total  supply  in 
the  ordinary  plowed  soil.  The  results  plainly  show,  however,  that  without  the 
addition  of  phosphorus  such  crops  cannot  be  grown  year  after  year.  Where 
no  phosphorus  has  been  applied,  the  crops  have  removed  only  120  pounds  of 
phosphorus  in  the  thirteen  years,  which  is  equivalent  to  only  10  percent  of  the 
total  amount  (1,200  pounds)  present  in  the  surface  soil  at  the  beginning  of  the 
experiment  in  1902.  The  total  phosphorus  applied  from  1902  to  1914,  as  an 
average  of  all  plots  where  it  has  been  used,  has  amounted  to  325  pounds  per  acre 
and  has  cost  $32.50.  This  has  paid  back  $97.20,  or  300  percent  on  the  invest- 
ment ; whereas  potassium,  used  in  the  same  number  of  tests  and  at  the  same  cost, 
has  paid  back  only  $2.20  per  acre  in  the  thirteen  years,  or  less  than  7 percent 
of  its  cost.  Are  not  these  results  to  be  expected  from  the  composition  of  such 
soil  and  the  requirements  of  crops?  (See  Table  2,  page  5,  and  also  Table  A 
in  the  Appendix.) 

Nitrogen  was  applied  to  this  field,  in  commercial  form  only,  from  1902  to 
1905;  but  clover  was  grown  in  1906  and  1910,  and  a cover  crop  of  cowpeas  after 
the  clover  in  1906.  The  cowpeas  were  plowed  under  on  all  plots,  and  the  1910 


102 

103 

104 

105 

106 

107 

108 

109 

0 

R 

P 

K 

RP 

RK 

PK 

RPK 

$186.76 

$193.83 

$286.61 

$190.53 

$285.03 

$191.10 

$294.91 

$284.47 

Plate 

6. — Crop 

Values  for 

Thirteen 

Years,  Bloomington 

Experiment 

Field 

(R=residues;  P— phosphorus;  K=potassium,  or  kalium) 


1915 ] 


Lake  County 


21 


clover  (except  the  seed)  was  plowed  under  on  five  plots  (103,  106,  107,  109,  and 
110).  Straw  and  corn  stalks  have  also  been  returned  to  these  plots  in  recent 
years.  The  effect  of  returning  these  residues  to  the  soil  has  been  appreciable  since 
1910  (an  average  increase  on  Plots  106  and  109  of  4.5  bushels  of  wheat,  5.4  bushels 
of  corn,  and  4.3  bushels  of  oats)  and  probably  will  be  more  marked  on  subse- 
quent crops.  Indeed,  the  large  crops  of  corn,  oats,  and  wheat  grown  on  Plots 
104  and  108  during  the  thirteen  years  have  drawn  their  nitrogen  very  largely 
from  the  natural  supply  in  the  organic  matter  of  the  soil.  The  roots  and  stubble 
of  clover  contain  no  more  nitrogen  than  the  entire  plant  !, from  the  soil 
alone,  but  they  decay  rapidly  in  contact  with  the  soil  av.>!  [M.  bably  hasten  the 
decomposition  of  the  soil  humus  and  the  consequent  libera tm:i  f the  soil  nitro- 
gen. But  of  course  there  is  a limit  to  the  reserve  stock  of  humus  and  nitrogen 
remaining  in  the  soil,  and  the  future  years  will  undoubtedly  witness  a gradually 
increasing  difference  between  Plots  104  and  106,  and  between  Plots  108  and  109, 
in  the  yields  of  grain  crops. 

Plate  6 shows  graphically  the  relative  values  of  the  thirteen  crops  for  the 
eight  comparable  plots,  Nos.  102  to  109.  The  cost  of  the  phosphorus  is  indicated 


Table  10. — Fertility  in  the  Soils  op  Lake  County,  Illinois 
Average  pounds  per  acre  in  4 million  pounds  of  subsurface  (about  6%  to  20  inches) 


Soil 

Total 

Total 

Total 

Total 

Total 

Total 

Lime- 

Soil 

type 

Soil  type 

organic 

nitro- 

phos- 

potas- 

magne- 

cal- 

stone 

acid- 

No. 

carbon 

gen 

phorus 

sium 

sium 

cium 

present 

ity 

Upland  Prairie  Soils 


| Brown  silt  loam 

91  050 

7 940 1 1 960 

101  020] 29  810|  19  310 

1 110 

Brown  sandy  loam 

4 280 

440 1 1 000 

53  720  7 200 | 12  080 

| 40 

Upland  Timber  Soils 


1234 

Yellow-gray  silt  loam. . . 

26 

090 

2 630 

1 300 

106 

140 

31 

660 

14  190 

310 

1035 

Yellow  silt  loam 

23 

980 

2 720 

1 620 

136 

020 

40 

600 

13  460 

60 

1064 

Yellow-gray  sandy  loam. 

18 

960 

2 040 

1 840 

71 

040 

19 

920 

17  560 

160 

1064.4 

Yellow-gray  sandy  loam 

on  gravel  

10 

000 

680 

1 000 

69 

640 

13 

920 

20  520 

40 

1281 

Dune  sand  

18  520 

720 

1 160 

53 

840 

14 

280 

18  040 

80 

1090 

Gravelly  loam  

16 

200 

1 760 

1 600 

66  560 

52 

600 

75  920 

255  400 

Terrace  Soils 


1527 

Brown  silt  loam  over 

gravel 

55  560 

4 760 

1 680 

78  440 

16  920 

14  880 

200 

1564.4 

Yellow-gray  sandy  loam 

on  gravel  

30  320 

2 400 

2 080 

86  880 

24  880 

15  160 

160 

1560.4 

Brown  sandy  loam  on 

gravel  

21  080 

2 200 

1 200 

82  440 

28  160 

36  240 

72  520 

1590.4 

Gravelly  loam  on  gravel. 

32  240 

2 840 

2 360 

77  880 

21  280 

19  200 

2 720 

Swamp  and  Bottom-Land  Soils 


1401 

Deep  peat  (slightly  de- 

composed moss)  

988  560 

32  700 

1 000 

3 820 

7 640 

18  080 

1 940 

1401 

Deep  peat  

535  240 

66  050 

2 410 

8 180 

11  880 

53  010 

460 

1402 

Medium  peat  on  clay 

295  140 

24  820 

2 140 

33  480 

18  500 

38  660 

3 860 

1402.2 

Medium  peat  on  sand 

388  940 

25  020 

1 340 

15  200 

15  400 

35  760 

8 540 

1403 

Shallow  peat  on  clay. . . 

181  560 

14  680 

2 160 

86  360 

80  880 

151  040 

440  800 

1410 

Peaty  loam  

40  620 

3 760 

1 300 

52  460 

47  720 

79  200 

264  300 

1450 

Black  mixed  loam 

115  760 

9 840 

2 600 

78  400 

24  920 

33  560 

4 400 

1454 

Mixed  loam  (bottom 

land)  

117  340 

10  140 

3 320 

72  840 

94  240 

191  800 

Often 

1482 

Beach  sand 

6 080 

240 

600 

32  280 

23  080 

36  400 

25  760 

Soil  Report  No.  9 


[April, 


22 


by  that  part  of  the  diagram  above  the  short  crossbars.  It  should  be  kept  in 
mind  that  no  value  is  assigned  to  clover  plowed  under  except  as  it  reappears  in 
the  increase  of  subsequent  crops.  Plots  106  and  109  are  heavily  handicapped 
because  of  the  clover  failure  on  those  plots  in  1906  and  the  poor  yield  of  clover 
seed  in  1910,  whereas  Plots  104  and  108  produced  a fair  crop  in  1906  and  a very 
large  crop  in  1910.  Plot  106,  which  receives  the  most  practical  treatment  for 
permanent  agriculture  (RLP),  has  produced  a total  value  in  thirteen  years  only 
$1.58  below  that  from  Plot  104  (LP).  (See  also  table  on  last  page  of  cover.) 

The  Subsurface  and  Subsoil 

In  Tables  10  and  11  are  recorded  the  amounts  of  plant  food  in  the  subsur- 
face and  the  subsoil  strata  of  the  Lake  county  soils,  but  it  should  be  remembered 
that  these  supplies  are  of  little  value  unless  the  top  soil  is  kept  rich.  Probably 
the  most  important  information  contained  in  these  tables  is  that  the  subsoils 
are  usually  rich  in  limestone.  This  fact  probably  accounts  for  the  moderate 
success  with  alfalfa  on  some  Lake  county  farms,  even  where  limestone  has  not 
been  applied.  If  alfalfa  is  given  a good  start  with  manure  or  by  a favorable 
season,  until  the  roots  reach  the  limestone  subsoil,  subsequent  addition  of  lime- 
stone to  the  plowed  soil  may  not  be  of  much  importance. 


Table  11. — Fertility  in  the  Soils  op  Lake  County,  Illinois 
Average  pounds  per  acre  in  6 million  pounds  of  subsoil  (about  20  to  40  inches) 


Soil 

typo 

No. 

Soil  type 

Total 

organic 

carbon 

Total 

nitro- 

gen 

Total  1 Total 
phos-  I potas- 
phorus  sium 

Total 

magne- 

sium 

Total 

cal- 

cium 

Lime- 

stone 

present 

Soil 

acid- 

ity 

Upland  Prairie  Soils 

1226 

Brown  silt  loam . . . . 

. 1 33  940 

3 350 

1 2 480  1 158  810 1 167  400 1 257  290 

| 998  570 1 

1060 

Brown  sandy  loam. . 

. 1 6 420 | 

660 1 

1 500  | 80  580 | 

10  800| 

18  120 

60 

Upland  Timber  Soils 


1234 

Yellow-gray  silt  loam 

27  080 

2 970 

2 470 

157  500 

165  470 

261  330 

1 066  470 

1035 

Yellow  silt  loam 

22  380 

14  700 

2 460 

178  710 

198  000 

263  940 

1 179  780 

1064.4 

Yellow-gray  sandy 

loam  on  gravel. . . . 

23  100 

1 680 

2 340 

119  880 

45  060 

36  000 

60 

1281 

Dune  sand  

27  780 

1 080 

1 740 

80  760 

21  420 

27  060 

120 

1090 

Gravelly  loam 

24  300 

2 640 

2 400 

99  840 

78  900 

113  880 

383  100 

Terrace  Soils 


1527 

1560.4 

Brown  silt  loam  over 

gravel  

Brown  sandy  loam  on 
gravel  

29  040 
12  960 

2 760 
1 380 

1 2 220 

2 520 

124  440 
108  360 

42  180 
176  880 

34  500 
278  340 

32  220 
1 232  460 

Swamp  and  Bottom-Land  Soils 

1401 

Deep  peat  (slightly  de- 

composed moss)  . . 

1 443  030 

48  870 

1 170 

6 060 

9 900 

30  600 

2 310 

1401 

Deep  peat 

1 269  080 

99  070 

3 620 

12  270 

17  820 

79  520 

690 

1402 

Medium  peat  on  clay. 

99  180 

6 840 

2 760 

165  780 

200  640 

323  040 

1 258  860 

1402.2 

Medium  peat  on  sand 

55  980 

3 000 

1 860 

34  860 

91  620 

153  840 

478  020 

1403 

Shallow  peat  on  clay. 

58  560 

3 360 

2 280 

127  260 

209  400 

589  860 

1 980  120 

1410 

Peaty  loam  

19  410 

1 260 

1 350 

85  050 

111  030 

183  510 

744  390 

1450 

Black  mixed  loam. . . . 

43  620 

3 420 

1 980 

122  880 

57  060 

74  760 

183  840 

1454 

Mixed  loam  (bottom 

land) 

72  480 

5 730 

4 380 

112  470 

140  400 

349  710 

Often 

1482 

Beach  sand  

9 120 

360 

900 

48  420 

34  620 | 

54  600 

38  640 



1915 ] 


Lake  County 


23 


INDIVIDUAL  SOIL  TYPES 
(a)  Upland  Prairie  Soils 

The  upland  prairie  soils  of  Lake  county  cover  140.38  square  miles,  or  29.08 
percent  of  the  entire  area  of  the  county.  They  are  usually  quite  dark  in  color, 
owing  to  their  large  organic-matter  content.  They  occupy  the  less  rolling  and 
comparatively  level  land. 

Brown  Silt  Loam  (1026  and  1226) 

Brown  silt  loam  is  a very  important  and  somewhat  extensive  type  in  this 
county,  covering  an  area  of  137.50  square  miles,  or  28.48  percent  of  the  entire 
area  of  the  county.  It  occupies  much  of  the  less  rolling  land,  a considerable  pro- 
portion of  which  needs  artificial  drainage.  The  presence  of  kettle-holes  in  some 
places  makes  complete  drainage  rather  difficult ; and  small  ponds  are  frequently 
found.  Many  local  areas  of  yellow-gray  silt  loam,  sandy  loam,  and  peat,  too 
small  to  show  on  the  map,  are  also  interspersed. 

The  surface  soil,  0 to  6%  inches,  is  a brown  silt  loam,  varying  from  a yel- 
lowish brown  on  the  more  rolling  areas  to  a dark  brown  or  black  on  the  more 
nearly  level  and  poorly  drained  tracts.  In  physical  composition  it  varies  to  some 
extent,  but  normally  contains  from  50  to  70  percent  of  the  different  grades  of 
silt.  The  clay  content,  as  well  as  the  organic-matter  content,  increases  as  the 
type  approaches  the  black  mixed  loam  (1450)  of  the  swampy  areas.  On  account 
of  the  complex  character  of  the  type,  the  amount  of  organic  matter  also  is  quite 
variable,  ranging  from  5.5  to  9.9  percent,  but  it  averages  about  7.6  percent,  or 
76  tons  per  acre.  Where  this  type  passes  into  the  yellow-gray  silt  loam,  the  con- 
tent of  organic  matter  becomes  much  lower  and  the  type  much  more  variable. 
The  slightly  higher  points,  perhaps  not  more  than  a fraction  of  an  acre  in  ex- 
tent, may  be  decidedly  gray  or  yellow,  while  the  lower  adjoining  parts  may  be 
quite  dark,  thus  giving  an  extremely  variable  phase  of  brown  silt  loam  impos- 
sible to  indicate  on  the  soil  map. 

The  subsurface  is  represented  by  a stratum  varying  from  6 to  15  inches  in 
thickness.  . This  variation  is  due  to  changing  topography  and  the  effect  of  ero- 
sion, the  stratum  becoming  thinner  on  the  more  rolling  areas.  Less  organic  mat- 
ter has  accumulated  on  the  more  rolling  areas  than  on  the  more  nearly  level 
tracts,  and  to  a less  depth.  In  physical  composition  the  subsurface  varies  the 
same  as  the  surface  soil,  but  it  normally  contains  a slightly  larger  amount  of 
clay  and  a smaller  amount  of  organic  matter.  The  organic  matter  varies  from 
2.7  to  4.2  percent,  with  an  average  of  3.8  percent,  or  38  tons  per  acre,  or  half  as 
much  as  is  in  the  surface  soil.  In  color  the  subsurface  varies  from  a dark 
brown  or  almost  black  to  a light  yellowish  brown ; it  becomes  lighter  with  depth, 
passing  into  the  subsoil  at  from  12  to  22  inches. 

The  natural  subsoil  begins  12  to  22  inches  beneath  the  surface  and  extends 
to  an  indefinite  depth  but  is  sampled  to  40  inches.  It  varies  from  a yellow  to  a 
drabbish  yellow  clayey  material  sometimes  composed  of  boulder  clay,  or  drift. 
In  some  of  the  flat  areas  where  material  has  washed  in  from  the  higher  sur- 
rounding parts,  the  subsoil  to  a depth  of  40  inches  does  not  reach  the  boulder 


24 


Soil  Report  No.  9 


[April, 


clay.  In  many  cases  the  stratum  of  gravel  at  16  to  20  inches  interferes  with  the 
collecting  of  samples. 

Where  properly  drained,  brown  silt  loam  requires  only  the  addition  of  phos- 
phorus, limestone,  and  organic  manures  for  the  improvement  and  permanent 
maintenance  of  its  productive  power.  As  an  average,  phosphorus  is  present  in 
the  plowed  soil  of  an  acre  to  the  extent  of  1,400  pounds,  compared  with  about 
7,500  pounds  of  nitrogen  and  47,000  pounds  of  potassium,  altho  the  lighter 
phase,  as  where  the  type  is  much  worn,  contains  as  low  as  1,200  pounds  of  phos- 
phorus and  5,000  of  nitrogen.  No  long-continued  field  experiments  have  been 
conducted  by  the  University  on  this  type  of  soil  in  the  late  Wisconsin  glaciation, 
but  the  results  already  reported  from  the  fields  at  Urbana,  Sibley,  and  Blooming- 
ton (pages  9,  15,  and  17),  considered  together  with  the  composition  of  the  soil, 
leave  no  doubt  as  to  the  wisdom  of  adding  phosphorus  to  this  soil  and  of  the 
foolishness  of  spending  money  for  potassium. 

This  type  contains  no  limestone  to  a depth  of  20  to  30  inches,  and  liberal 
use  of  this  material  should  prove  beneficial  for  clover  and  alfalfa,  even  tho  the 
lower  subsoil  usually  contains  abundance  of  limestone.  Farm  manures,  crop 
residues,  or  legume  crops  plowed  under  are  needed,  not  only  to  provide  nitrogen, 
but  also  to  give  activity  to  the  soil  for  the  liberation  of  plant  food  and  to  main- 
tain good  tilth,  or  good  physical  condition. 

Brown  Sandy  Loam  (1060  and  1260) 

Brown  sandy  loam  occupies  only  a small  area  in  the  county,  amounting  to 
2.88  square  miles,  1,844  acres,  or  .6  percent  of  the  entire  area. 

The  surface  soil,  0 to  6%  inches,  consists  of  a brown  sandy  loam  varying 
from  a light  or  yellowish  brown  to  a dark  brown  or  even  black  color.  The  areas 
in  the  western  part  of  the  country  are  of  the  lighter  colored  phase,  while  those 
in  the  eastern  part,  particularly  north  of  Waukegan,  partake  somewhat  of  the 
nature  of  peaty  loam  and  vary  toward  that  type. 

The  subsurface,  6%  to  18  or  20  inches,  consists  of  a brown  sandy  loam  vary- 
ing with  the  surface.  In  the  western  areas  it  is  quite  light  in  color,  varying  to 
yellow.  In  the  eastern  part  of  the  county,  it  is  somewhat  dark,  and  with  depth 
becomes  somewhat  gray  or  drab,  indicating  poorer  drainage  in  many  cases. 

The  subsoil  is  quite  variable,  in  some  places  passing  into  a yellowish  sand, 
in  others  into  a gravelly  till,  while  in  others  it  becomes  a drab  or  bluish-colored 
sand.  This  last  is  in  the  poorly  drained  areas. 

This  type  of  soil  requires  for  its  improvement  large  use  of  organic  matter. 
Being  loose  and  better  aerated  than  the  brown  silt  loam,  it  suffers  greater  loss 
of  that  constituent,  hence  greater  difficulty  is  found  in  maintaining  it.  Crop 
residues,  legume  crops,  and  manure  must  constitute  the  chief  materials  by  which 
the  organic-matter  content  is  maintained.  In  phosphorus  content,  this  type  is 
the  poorest  in  the  county,  and  it  is  also  very  deficient  in  limestone.  While  the 
potassium  content  is  large  (25,000  pounds  per  acre  of  plowed  soil),  it  is  in  part 
locked  up  in  sand  grains;  hence,  if  satisfactory  yields  of  legumes  are  not  secured 
where  the  soil  is  well  drained  and  treated  with  limestone  and  phosphorus,  the 
addition  of  kainit  or  potassium  chlorid  may  well  be  tried. 


1915 ] 


Lake  County 


2$ 


(b)  Upland  Timber  Soils 

The  upland  forest  soils  are  deficient  in  organic  matter  owing  to  the  fact  that 
the  vegetable  material  from  trees  accumulates  upon  the  surface  and  is  either 
burned  or  suffers  almost  complete  decay.  Grasses  which  furnish  large  quantities 
of  humus-forming  roots  do  not  grow  to  any  large  extent  in  forests.  At  the  same 
time,  the  organic  matter  that  had  accumulated  before  timber  began  growing  on 
these  soils  is  being  removed  thru  various  decomposition  processes,  with  the  result 
that  the  content  has  become  too  low  for  best  growth. 

Yellow-Gray  Silt  Loam  (1034  and  1234) 

Yellow-gray  silt  loam  is  the  most  important  and  extensive  soil  type  in  Lake 
county.  It  is  very  irregularly  distributed,  but  occupies  mostly  the  rolling  mo- 
rainal areas.  This  type  covers  196.01  square  miles,  125,447  acres,  or  40.59  per- 
cent of  the  county.  It  varies  greatly  in  topography — from  the  characteristic  bil- 
lowy, or  knob-and-basin,  features  of  the  moraines  to  the  almost  level  morainal 
and  intermorainal  tracts. 

The  surface  soil,  0 to  6%  inches,  is  a gray  or  yellowish  gray  silt  loam,  inco- 
herent and  mealy,  but  not  granular.  The  physical  composition  varies  a great 
deal  because  of  the  removal  by  erosion  in  some  places  of  the  thin  covering  of 
loess,  thus  exposing  the  variable  drift.  Many  local  areas  of  sandy  or  gravelly 
loam  are  found  in  this  type,  but  they  are  too  small  to  be  shown  on  the  map. 
Likewise  many  small  areas  of  dark  soil  such  as  the  brown  silt  loam  or  black 
mixed  loam  are  found  in  the  slight  depressions;  these  are  also  too  small  to  be 
shown.  The  amount  of  organic  matter  contained  in  the  surface  soil  of  this  type 
varies  from  1.8  to  3.6  percent,  with  an  average  of  2.7,  or  27  tons  per  acre.  This 
wide  variation  is  due  to  the  relation  of  the  type  to  other  types,  the  content  of 
organic  matter  increasing  where  it  grades  into  brown  silt  loam  (1026  or  1226) 
and  decreasing  where  it  passes  into  yellow  silt  loam  (1035  or  1235).  In  some 
places  erosion  has  reduced  the  content  of  organic  matter  much  below  the  normal, 
so  that  many  small  areas  are  yellow  in  color. 

The  subsurface  stratum  varies  from  3 to  10  inches  in  thickness,  being  thin- 
ner on  the  more  rolling  areas.  In  color  it  is  gray,  grayish  yellow,  or  yellow,  some- 
what pulverulent,  but  becoming  more  coherent  and  plastic  with  depth.  On  some 
of  the  areas  a stratum  of  gravel  an  inch  or  two  in  thickness  is  encountered  at  a 
depth  of  10  to  24  inches.  This  is  formed  by  the  washing  out  of  the  fine  material 
from  the  surface  drift,  as  may  be  seen  on  the  surface  of  exposed  drift  at  the 
present  time.  It  has  subsequently  been  covered  with  a thin  deposit  of  loess. 
The  amount  of  organic  matter  is  very  low,  amounting  to  only  1.1  percent,  or 
22  tons  per  acre,  for  a stratum  lSys  inches  in  thickness. 

The  subsoil  is  a yellow  to  a grayish  yellow  boulder  clay.  The  deeper  sub- 
soil contains  large  amounts  of  limestone  and  shows  brisk  effervescence  with 
hydrochloric  acid. 

In  the  management  of  this  yellow-gray  silt  loam,  one  of  the  most  essential 
points  is  the  maintenance  or  increase  of  the  organic  matter.  This  is  much  more 
necessary  with  this  type  than  with  the  brown  silt  loam,  because  this  soil  is  natur- 
ally much  more  deficient  in  that  constituent.  The  organic  matter  supplies  nitro- 
gen, liberates  mineral  plant  food,  prevents  running  together,  and  on  some  of  the 


Soil  Beport  No.  9 


[April, 


26 

more  rolling  areas,  prevents  washing  as  well  as  gives  better  tilth  to  the  soil  under 
all  conditions. 

Another  essential  is  the  application  of  ground  limestone,  so  that  clover, 
alfalfa,  and  other  legumes  may  be  grown  more  successfully.  In  many  cases  where 
limestone  is  present  in  the  subsoil,  the  legume  crops  will  grow  very  well,  but  fre- 
quently their  growth  may  be  profitably  increased  by  the  application  of  2 to  5 
tons  per  acre  of  limestone.  Potassium  is  exceedingly  abundant  in  this  type  of 
soil,  while  phosphorus  is  markedly  deficient,  as  is  readily  seen  from  the  tabular 
statements,  which  are  well  supported  by  the  results  already  secured  from  the  soil 
experiment  field  conducted  for  many  years  by  the  University  of  Illinois  with  the 
helpful  cooperation  of  Mr.  D.  M.  White,  on  his  farm  near  Antioch  in  Lake 
county.  (See  Tables  3 and  4,  pages  7 and  8.) 

Yellow  Silt  Loam  (1035  and  1235) 

Yellow  silt  loam  is  found  chiefly  in  the  west  quarter  of  the  county  where  the 
highest  part  of  the  Valparaiso  moraine  occurs.  The  type  here  is  not  due  pri- 
marily to  erosion,  as  in  most  parts  of  the  state,  but  to  the  irregularities  produced 
in  the  piling  up  of  the  morainic  material.  Basin-like  kettle-holes  are  found  vary- 
ing from  25  feet  or  less  to  75  and  possibly  100  feet  in  depth.  Rounded  knobs  are 
also  quite  characteristic  of  this  moraine.  The  area  of  this  type  amounts  to  38.5 
square  miles,  24,639  acres,  or  8 percent  of  the  county. 

The  surface  soil,  0 to  6%  inches,  is  a yellow  or  yellowish  gray  silt  loam, 
usually  containing  some  sand  and  gravel.  This  stratum  is  usually  formed  from 
drift  material,  the  loess,  if  there  ever  was  any,  having  been  removed  by  erosion. 
Owing  to  its  derivation,  the  stratum  varies  a great  deal  in  physical  composition. 
The  organic-matter  content  averages  about  1.8  percent. 

The  subsurface  is  composed  of  yellow  drift  material,  as  is  also  the  subsoil. 

One  of  the  best  ways  to  manage  this  type  is  to  keep  it  in  permanent  pasture. 
As  a rule,  it  cannot  be  satisfactorily  cropped  in  ordinary  rotations,  altho  it  may 
be  used  very  successfully  for  long  rotations  with  much  pasture  or  meadow. 

Where  this  soil  has  been  long  cultivated  and  thus  exposed  to  surface  wash- 
ing, it  is  particularly  deficient  in  nitrogen ; indeed,  on  such  lands  the  low  supply 
of  nitrogen  is  the  factor  that  first  limits  the  growth  of  grain  crops.  This  fact  is 
very  strikingly  illustrated  by  the  results  from  two  pot-culture  experiments  re- 
ported in  Tables  12  and  13,  and  illustrated  in  Plates  7 and  8. 

In  one  experiment,  a large  quantity  of  the  typical  worn  hill  soil  was  col- 
lected from  two  different  places.1  Each  lot  of  soil  was  thoroly  mixed  and  put 
in  ten  four- gallon  jars.  Ground  limestone  was  added  to  all  the  jars  except  the 
first  and  last  in  each  set,  those  two  being  retained  as  control  or  check  pots.  The 
elements  nitrogen,  phosphorus,  and  potassium  were  added  singly  and  in  com- 
bination, as  shown  in  Table  12. 

As  an  average,  the  nitrogen  applied  produced  a yield  about  eight  times  as 
large  as  that  secured  without  the  addition  of  nitrogen.  While  some  variations 
in  yield  are  to  be  expected,  because  of  differences  in  the  individuality  of  seed  or 
other  uncontrolled  causes,  yet  there  is  no  doubting  the  plain  lesson  taught  by 
these  actual  trials  with  growing  plants. 

‘Soil  for  wheat  pots  from  loess-covered  unglaciated  area,  and  that  for  oat  pots  from 
upper  Illinois  glaciation. 


1915] 


Lake  County 


27 


The  question  arises  next,  Where  is  the  farmer  to  secure  this  much-needed 
nitrogen  ? To  purchase  it  in  commercial  fertilizers  would  cost  too  much ; indeed, 
under  average  conditions  the  cost  of  the  nitrogen  in  such  fertilizers  is  greater 
than  the  value  of  the  increase  in  crop  yields. 

But  there  is  no  need  whatever  to  purchase  nitrogen,  for  the  air  contains  an 
inexhaustible  supply  of  it,  which,  under  suitable  conditions,  the  farmer  can  draw 
upon,  not  only  without  cost,  but  with  profit  in  the  getting.  Clover,  alfalfa,  cow- 
peas,  and  soybeans  are  not  only  worth  raising  for  their  own  sake,  but  they  have 
the  power  to  secure  nitrogen  from  the  atmosphere  if  the  soil  contains  the  essen- 
tial minerals  and  the  proper  nitrogen-fixing  bacteria. 

In  order  to  secure  further  information  along  this  line,  another  experiment 
with  pot  cultures  was  conducted  for  several  years  with  the  same  type  of  worn  hill 
soil  as  that  used  in  the  former  experiment.  The  results  are  reported  in  Table  13. 

To  three  pots  (Nos.  3,  6,  and  9)  nitrogen  was  applied  in  commercial  form, 
at  an  expense  amounting  to  more  than  the  total  value  of  the  crops  produced.  In 
three  other  pots  (Nos.  2,  11,  and  12)  a crop  of  cowpeas  was  grown  during  the 
late  summer  and  fall  and  turned  under  before  the  wheat  or  oats  were  planted. 


Plate  7.— Wheat  in  Pot-Cultuke  Experiment  with  Yellow  Silt  Loam  of  Worn  Hill  Land 
(See  Table  12) 


Table  12. — Crop  Yields  in  Pot-Culture  Experiment  with  Yellow  Silt  Loam  of  Worn 

Hill  Land 
(Grams  per  pot) 


Pot 

No. 

1 None 

2 Limestone . 


Soil  treatment  applied 


3 Limestone,  nitrogen 

4 Limestone,  phosphorus 

5 Limestone,  potassium 

6 Limestone,  nitrogen,  phosphorus. . 

7 Limestone,  nitrogen,  potassium  . . . 

8 Limestone,  phosphorus,  potassium, 


9 

10 


Limestone,  nitrogen,  phosphorus,  potassium. 
None 


Wheat 


Oats 


3 5 


4 

26 

3 


4 

45 

6 


3 

34“ 

33 
2 

34 
3 


5 

38 

46 

5 

38 

5 


Average  yield  with  nitrogen i 32  42 

Average  yield  without  nitrogen I 3 5 


Average  gain  for  nitrogen 


29  37 


Soil  Report  No.  9 


[April, 


28 

Pots  1 and  8 served  for  important  comparisons.  After  the  second  cover  crop  of 
cowpeas  had  been  turned  under,  the  yield  from  Pot  2 exceeded  that  from  Pot  3 ; 
and  in  the  subsequent  years  the  legume  green  manures  produced,  as  an  average, 
rather  better  results  than  the  commercial  nitrogen.  This  experiment  confirms 
that  reported  in  Table  12,  in  showing  the  very  great  need  of  nitrogen  for  the 
improvement  of  this  type  of  soil,  and  it  also  shows  that  nitrogen  need  not  be 
purchased  but  that  it  can  be  obtained  from  the  air  by  growing  legume  crops  and 
plowing  them  under  as  green  manure.  Of  course  the  soil  can  be  very  markedly 
improved  by  feeding  the  legume  crops  to  live  stock  and  returning  the  resulting 
farm  manure  to  the  land,  if  legumes  are  grown  frequently  enough  and  if  the  farm 
manure  produced  is  sufficiently  abundant  and  is  saved  and  applied  with  care. 

As  a rule,  it  is  not  advisable  to  try  to  enrich  this  type  of  soil  in  phosphorus, 
for  with  the  erosion  that  is  sure  to  occur  to  some  extent  the  phosphorus  supply 
will  be  renewed  from  the  subsoil. 

One  of  the  most  profitable  crops  to  grow  on  this  land  is  alfalfa.  To  get 
alfalfa  well  started  may  require  the  use  of  limestone,  thoro  inoculation  with 
nitrogen-fixing  bacteria,  and  a moderate  application  of  farm  manure.  If  manure 
is  not  available,  it  is  well  to  apply  about  500  pounds  per  acre  of  acid  phosphate 
or  steamed  bone  meal,  mix  it  with  the  soil,  by  disking  if  possible,  and  then  plow 
it  under.  The  limestone  (if  needed)  should  be  applied  after  plowing  and  should 
be  mixed  with  the  surface  soil  in  the  preparation  of  the  seed  bed.  The  special 


Plate  8.— Wheat  in  Pot-Cultuke  Experiment  with  Yellow  Silt  Loam  of  Worn  Hill  Land 
(See  Table  13) 


Table  13. — Crop  Yields  in  Pot-Culture  Experiment  with  Yellow  Silt  Loam  of  Worn  Hill 
Land  and  Nitrogen-Fixing  Green  Manure  Crops 

(Grams  per  pot) 


Pot 

No. 

Soil  treatment 

1903 

Wheat 

1904 

Wheat 

1905 

Wheat 

1906 

Wheat 

| 1907 
Oats 

1 

None  

5 

4 

4 

4 

6 

2 

Limestone,  legume  

10 

17 

26 

19 

37 

11 

Limestone,  legume,  phosphorus  

14 

19 

20 

18 

27 

12 

Limestone,  legume,  phosphorus,  potassium. . 

16 

20 

21 

19 

30 

3 

Limestone,  nitrogen  

17 

14 

15 

9 

28 

0 

Limestone,  nitrogen,  phosphorus  

26 

20 

18 

18 

30 

9 

Limestone,  nitrogen,  phosphorus,  potassium 

31 

34 

21 

20 

26 

8 

Limestone,  phosphorus,  potassium  

3 

3 

5 

3 

7 

1915 ] 


Lake  County 


29 


purpose  of  this  treatment  is  to  give  the  alfalfa  a quick  start  in  order  that  it  may 
grow  rapidly  and  thus  protect  the  soil  from  washing. 

Yellow-Gray  Sandy  Loam  (1064) 

Yellow-gray  sandy  loam  occupies  only  small  areas  in  Lake  county,  amount- 
ing to  488  acres.  It  is  practically  all  found  in  the  western  part  in  the  most 
broken  of  the  morainal  ridges. 

The  surface  soil,  0 to  6%  inches,  is  a yellow  or  grayish  yellow  sandy  loam, 
frequently  containing  from  15  to  25  percent  of  gravel.  In  some  small  areas  this 
gravel  may  be  absent ; its  presence  is  due  to  the  fact  that  the  soil  is  made  of  a 
sandy  till.  The  organic-matter  content  is  1.8  percent,  or  about  18  tons  per  acre. 

The  subsurface  stratum,  from  3 to  8 inches  in  thickness,  differs  from  the 
surface  in  being  of  a lighter  color,  owing  to  the  smaller  amount  of  organic  mat- 
ter present,  about  .3  percent.  At  a depth  of  about  12  to  16  inches  on  much  of 
this  type,  a stratum  of  gravelly  material  exists  thru  which  it  is  practically  im- 
possible to  bore  with  an  auger. 

The  subsoil  varies  from  a somewhat  gravelly  till  to  almost  pure  sand. 

For  the  improvement  of  this  type,  the  addition  of  organic  matter  and  nitro- 
gen is  very  essential,  and  limestone  should  be  applied  liberally  for  the  best  re- 
sults with  legumes.  The  porous  subsoil  affords  such  a deep  feeding  range  for 
plant  roots  that  the  addition  of  phosphorus  is  not  likely  to  be  necessary  or  profit- 
able. 

Yellow-Gray  Sandy  Loam  on  Gravel  (1064.4) 

Yellow-gray  sandy  loam  on  gravel  occurs  only  in  the  northwestern  part  of 
the  county,  and  there  in  limited  areas.  The  type  differs  but  little  from  yellow- 
gray  sandy  loam  except  that  it  contains  much  more  gravel  in  the  subsoil  and  for 
that  reason  is  less  desirable.  It  occupies  1.48  square  miles,  or  .3  percent  of  the 
entire  area  of  the  county.  The  stratum  of  gravel  varies  a great  deal,  both  as  to 
depth  and  physical  composition.  In  depth  it  varies  from  12  to  30  inches ; in 
composition  it  is  sandy,  or  a sand  in  some  places,  and  in  others  a mixture  of 
sand,  gravel,  and  small  stones  not  over  two  inches  in  diameter. 

The  management  of  this  type  should  be  the  same  as  for  the  yellow-gray 
sandy  loam.  Alfalfa  does  fairly  well  on  this  type,  and  sweet  clover  would  do 
equally  well. 

Dune  Sand  (1081  and  1281) 

Dune  sand  is  found  in  the  vicinity  of  Fox  Lake,  and  also  along  the  old  lake 
shore  north  of  Waukegan.  It  covers  1.47  square  miles.  Its  presence  is  due  to 
the  action  of  wind,  and  possibly  the  waves,  in  piling  the  sand  up  from  the  lake 
shore.  The  surface  soil  contains  about  2.25  percent  of  organic  matter,  while  the 
subsurface  has  about  .8  percent. 

In  the  management  of  this  type,  limestone  should  be  applied  and  legume 
crops  should  be  prominent  in  the  rotation  unless  large  amounts  of  organic  mat- 
ter can  be  added  in  some  other  form.  The  only  other  addition  suggested  is  potas- 
sium, but  this  should  not  be  applied  on  a large  scale  unless  found  profitable  by 
careful  trial  on  small  areas. 


30 


Soil  Report  No.  9 


[April, 


For  results  from  field  experiments  on  sand  soil,  see  pages  246  to  249  of 
Bulletin  123  of  this  station.1  In  the  experiments  there  described  (conducted  in 
Tazewell  county),  the  average  value  of  the  increase  per  acre  per  annum  was 
$12.12  from  nitrogen,  $2.96  from  potassium  (costing  $2.50),  and  4 cents  from 
phosphorus,  the  order  of  crops  being  corn,  corn,  oats,  wheat,  corn,  corn.  The 
nitrogen  applied  cost  $15  in  commercial  form,  but  of  course  by  growing  legume 
crops,  which  are  worth  raising  for  their  own  sake,  that  element  may  be  secured 
from  the  air  without  cost. 

Gravelly  Loam  (1090  and  1290) 

Gravelly  loam  occurs  principally  in  the  morainal  regions  of  the  northwest 
part  of  the  Lake  county,  altho  some  small  areas  are  found  in  other  parts.  The 
total  area  aggregates  611  acres,  or  .2  percent  of  the  area  of  the  county. 

The  surface  soil  is  composed  of  a large  amount  of  gravel,  in  many  cases 
amounting  to  60  or  70  percent.  Occasionally  small  stones  an  inch  or  two  in 
diameter  are  found  mixed  with  the  gravel.  The  organic-matter  content  amounts 
to  approximately  3 percent,  or  30  tons  per  acre.  The  subsurface  soil  contains 
about  one-fourth  as  much  as  the  surface. 

This  type  is  of  very  little  agricultural  significance.  The  treatment  recom- 
mended is  the  same  as  that  for  yellow-gray  sandy  loam  (1064).  It  may  well  be 
left  in  permanent  pasture. 

(c)  Terrace  Soils 

Terrace  soils  occur  along  streams  and  were  formed  at  a time  when  the 
streams  were  much  larger  than  at  present  and  carried  large  amounts  of  coarse 
material,  such  as  sand  and  gravel.  This  Overloading  of  the  streams  caused 
deposition  along  their  courses  which  resulted  in  the  formation  of  terraces,  bench 
lands,  or  second  bottom  lands.  Fine  material,  later  deposited  over  this  sand  and 
gravel,  forms  the  present  soil. 

Brown  Silt  Loam  over  Gravel  (1527) 

Brown  silt  loam  over  gravel  is  found  along  the  Des  Plaines  river  near  the 
southern  part  of  the  county  where  the  stream  formed  its  widest  terrace.  The 
deposit  of  gravel  here  is  not  very  deep,  but  it  furnishes  a very  effective  means 
for  the  natural  drainage  of  these  areas.  This  type  occupies  1.85  square  miles. 

The  surface  soil,  0 to  6%  inches,  is  a brown  silt  loam,  with  some  sand,  but 
rarely  containing  enough  to  make  it  a sandy  loam.  The  average  amount  of 
organic  matter  present  is  5.4  percent,  or  54  tons  per  acre. 

The  subsurface  soil  consists  of  a brown  silt  loam,  becoming  yellow  at  about 
16  inches  and  passing  into  the  subsoil  at  a depth  of  18  inches.  The  subsurface 
stratum  contains  about  2.5  percent  of  organic  matter. 

The  subsoil  varies  a great  deal,  in  some  cases  containing  a considerable 
amount  of  sand  and  fine  gravel.  It  is  generally  a yellow  clayey  silt,  pervious, 
and  well  drained.  The  depth  to  the  gravel  varies  from  38  to  48  inches.  It  con- 
sists of  a mixture  of  medium  and  fine  gravel  with  some  coarse  sand. 

This  type  requires  practically  the  same  management  as  the  brown  silt  loam, 


'Bulletin  123  may  be  had  from  the  Experiment  Station  upon  request. 


1915 ] 


Lake  County 


31 


altho  in  some  cases  there  may  be  more  need  of  organic  matter  than  in  some  phases 
of  the  brown  silt  loam.  Alfalfa  should  do  well  on  this  type. 

Yellow-Gray  Sandy  Loam  on  Gravel  (1564.4) 

Yellow-gray  sandy  loam  on  gravel  occurs  only  along  the  Des  Plaines  river 
and  is  limited  largely  to  the  east  side  of  this  stream.  The  total  area  is  2.25 
square  miles. 

The  surface  soil,  0 to  6%  inches,  varies  in  color  from  a yellow  to  a gray,  and 
in  texture  from  a loam  to  a sand.  These  variations  are  so  limited  in  area  and 
so  badly  mixed  that  it  is  impossible  to  represent  them  on  the  map.  In  some 
places  there  are  slight  ridges  that  indicate  low  dunes ; these  give  rise  to  a very 
sandy  phase. 

The  subsurface  stratum  is  as  variable  as  the  surface.  In  small  areas  the 
subsurface  is  a sandy  clay  or  sandy  clay  loam,  while  in  others  it  is  a yellow  sand. 
The  organic-matter  content  of  the  subsurface  is  higher  in  the  more  silty  or  clayey 
parts,  but  in  the  more  sandy  phase  it  contains  almost  no  organic  matter. 

The  subsoil  varies  in  different  parts  of  the  Des  Plaines  valley.  In  the  north- 
ern part  it  is  decidedly  gravelly,  while  in  the  southern,  sand  prevails.  The  depth 
to  the  sand  or  gravelly  stratum  varies  from  over  30  inches  in  many  places  to 
less  than  15  inches  in  others. 

In  the  southern  half  of  the  county  this  type  is  not  under  cultivation,  but  is 
almost  entirely  covered  with  a young  growth  of  forest  trees.  Where  it  is  under 
cultivation,  the  treatment  should  be  about  the  same  as  for  the  yellow-gray  silt 
loam,  except  as  regards  phosphorus.  With  the  porous  character  of  the  soil  and 
subsoil,  and  the  extensive  feeding  range  thus  afforded  plants,  the  supply  of  phos- 
phorus naturally  contained  in  this  soil  should  be  adequate  for  large  crops. 

Brown  Sandy  Loam  on  Gravel  (1560.4) 

Brown  sandy  loam  on  gravel  is  found  principally  along  the  Des  Plaines 
river  and  is  similar  to  yellow-gray  sandy  loam  on  gravel  except  that  the  forests 
that  have  recently  grown  up  here  have  not  reduced  the  organic-matter  content 
to  such  a low  amount.  Part  of  the  type  in  the  southern  part  of  the  county  has 
never  been  covered  with  forest.  In  topography  the  type  shows  a slight  ridging, 
due  to  the  action  of  wind  in  forming  sand  dunes  or  of  the  water  in  forming  bars. 
The  total  area  is  2.4  square  miles,  or  .5  percent  of  the  area  of  the  county. 

The  surface  soil,  0 to  6%  inches,  varies  in  color  from  a light  to  a dark  brown, 
almost  black,  and  in  texture  from  a loam  to  a sandy  loam. 

The  subsurface  soil  is  a light  brown  loam  to  sandy  loam,  having  a thickness 
of  5 to  12  inches  with  an  average  of  9 to  10  inches.  It  passes  into  the  gravelly, 
sandy  subsoil,  which  is  made  up  of  medium  and  fine  gravel,  mixed  with  more  or 
less  coarse  sand.  The  depth  of  the  gravel  from  the  surface  varies  from  14  to  30 
inches  and  even  more  in  small  local  areas.  The  bed  of  gravel  itself  is  probably 
not  over  20  feet  in  depth  in  any  place,  and  toward  the  southern  part  of  the 
county  it  is  much  less  than  that.  In  many  places  it  is  being  taken  out  for  use 
on  roads.  The  presence  of  gravel  in  the  subsoil  gives  excellent  drainage  to  this 
type,  and  in  seasons  of  drouth,  the  crops  may  suffer  because  of  lack  of  moisture. 

Only  the  ordinary  crops,  as  a rule,  are  grown  on  this  type,  but  it  is  fairly 


32 


Soil  Keport  No.  9 


[April, 


well  adapted  to  the  growth  of  alfalfa  and  deep-rooting  crops.  Manure,  crop 
residues,  or  legume  crops  should  be  turned  under  in  order  to  maintain  the  or- 
ganic matter  and  nitrogen,  but  the  addition  of  phosphorus  is  not  likely  to  be 
profitable. 

Gravelly  Loam  on  Gravel  (1590.4) 

Gravelly  loam  on  gravel  covers  one  area  of  179  acres  in  Section  22,  Town 
46  North,  Range  11  East. 

The  surface  soil,  0 to  6%  inches,  consists  of  a brown,  gravelly  loam,  the 
gravel  present  amounting  to  60  to  75  percent.  The  content  of  organic  matter  is 
about  3 percent.  The  subsurface  stratum  contains  even  a larger  amount  of  gravel 
than  the  surface,  with  a proportionately  smaller  amount  of  organic  matter.  A 
sample  could  not  be  obtained  to  a depth  of  more  than  20  inches.  The  subsoil  con- 
sists of  various  grades  of  gravel  mixed  with  a few  small  stones. 

This  is  a very  poor  type  of  soil,  owing  to  the  fact  that  it  does  not  have  much 
power  for  retaining  moisture  in  times  of  drouth,  and  the  plant  food  leaches  out 
readily.  The  liberal  use  of  legume  crops  and  organic  manures  is  advised. 

(d)  Swamp  and  Bottom-Land  Soils 
Deep  Peat  (1401) 

Deep  peat  is  found  in  nearly  all  parts  of  Lake  county,  occurring  on  the  old 
beach  of  Lake  Michigan,  in  the  bottom  lands  of  the  streams,  in  the  depressions 
of  the  moraines,  and  around  the  margins  of  many  of  the  lakes.  The  total  area 
is  38.1  square  miles,  24,382  acres,  or  7.89  percent  of  the  area  of  the  county.  The 
deep  peat  is  formed  by  the  growth  of  both  grasses  and  mosses.  In  one  area  in 
Section  35,  Town  46  North,  Range  10  East,  the  peat  was  found  to  be  forming 
entirely  by  the  accumulation  of  the  sphagnum  moss,  independent  of  the  growth 
of  grasses ; in  other  areas,  both  grasses  and  mosses  contribute  to  the  deposit. 

The  surface  soil,  0 to  6%  inches,  is  a black  or  brown  peat,  more  or  less  de- 
composed. The  drained  areas  have  undergone  greater  decomposition  because  of 
better  aeration,  while  the  moss-covered  or  grass-covered  peat  of  the  undrained 
areas  has  changed  but  little.  The  content  of  organic  matter  varies  from  61  to  77 
percent,  with  an  average  of  70.5  percent. 

The  subsurface  soil,  6%  to  20  inches,  consists  of  black  or  brown  peat  that 
usually  shows  the  texture  of  the  material  from  which  it  was  produced. 

The  subsoil,  from  20  to  40  inches,  is  usually  a brown  peat,  altho  in  some 
small  areas  sand  or  silty  material  may  form  the  subsoil  below  30  inches.  This 
latter  phase  is  almost  invariably  drab  in  color,  due  to  deoxidation  b^  organic 
acids.  , I A 

Because  of  lack  of  drainage,  this  type  of  soil  in  Lake  county  has  not  been 
largely  cultivated,  except  in  the  small  areas.  It  does,  however,  supply  a large 
amount  of  hay  that  is  used  to  a considerable  extent  for  packing  ice  in  the  large 
ice  houses  on  the  shores  of  the  lakes.  As  a rule,  it  is  not  desirable  to  attempt  to 
drain  this  type  by  means  of  tiles  unless  they  can  be  laid  deep  enough  to  place 
them  in  the  clayey  or  silty  subsoil.  Tiles  laid  in  peat  soon  get  out  of  line. 

As  shown  in  Table  2,  deep  peat  contains  in  one  million  pounds  of  surface 
soil  about  32,000  pounds  of  nitrogen,  1,500  pounds  of  phosphorus,  and  3,900 


li)15 ] 


Lake  County 


33 


pounds  of  potassium.  This  shows  in  the  surface  6%  inches  of  an  acre  nearly  five 
times  as  much  nitrogen  as  the  brown  silt  loam  prairie.  In  phosphorus  content 
these  two  soil  types  are  about  equal,  but  the  peat  contains  less  than  one-tenth  as 
much  potassium  as  the  brown  silt  loam.  Thus  the  total  supply  of  potassium  in 
the  peat  to  a depth  of  7 inches  (3,900  pounds)  would  be  equivalent  to  the  potas- 
sium requirement  (73  pounds)  of  a hundred-bushel  crop  of  corn  for  only  53 
years ; or  if  the  equivalent  of  only  one-fourth  of  one  percent  of  this  is  annually 
available,  in  accordance  with  the  rough  estimate  suggested  in  Bulletin  123,  then 
about  10  pounds  of  potassium  would  be  liberated  annually,  or  sufficient  for  about 
14  bushels  of  corn  per  acre. 

In  Table  14  are  given  all  results  obtained  from  the  Manito  (Mason  county) 
experiment  field  on  deep  peat,  which  was  begun  in  1902  and  discontinued  after 
1905.  The  plots  in  this  field  were  one  acre1  each  in  size,  2 rods  wide  and  80  rods 
long.  Untreated  half -rod  division  strips  were  left  between  the  plots,  which,  how- 
ever, were  cropped  the  same  as  the  plots. 

The  results  of  four  years’  tests,  as  given  in  Table  14,  are  in  complete  har- 
mony with  the  information  furnished  by  the  chemical  composition  of  peat  soil 
as  compared  with  that  of  ordinary  normal  soils.  Where  potassium  was  applied, 
the  yield  was  from  three  to  four  times  as  large  as  where  nothing  was  applied. 
Where  approximately  equal  money  values  of  kainit  and  potassium  chlorid  were 
applied,  slightly  greater  yields  were  obtained  with  the  potassium  chlorid,  which, 
however,  supplied  about  one-third  more  potassium  than  the  kainit.  On  the  other 
hand,  either  material  furnished  more  potassium  than  was  required  by  the  crops 
produced. 

The  use  of  700  pounds  of  sodium  chlorid  (common  salt)  produced  no  appre- 
ciable increase  over  the  best  untreated  plots,  indicating  that  where  potassium  is 
itself  actually  deficient,  salts  of  other  elements  cannot  take  its  place. 

Applications  of  2 tons  per  acre  of  ground  limestone  produced  no  increase  in 
the  corn  crops,  either  when  applied  alone  or  in  combination  with  kainit,  either 
the  first  year  or  the  second. 

Table  14. — Coen  Yields  in  Soil  Experiments,  Manito  Field;  Typical  Deep  Peat  Soil 
(Bushels  per  acre) 


Plot 

No. 

Soil  treatment 
for  1902 

Corn 

1902 

Corn 

1903 

Soil  treatment 
for  1904 

Corn 

1904 

Corn 

1905 

Four 

crops 

1 

None 

10.9 

8.1 

None 

17.0 

12.0 

48.0 

42.9 

2 

None 

10.4 

10.4 

Limestone,  4000  lbs .... 

12.0 

10.1 

3 

Kainit,  600  lbs 

30.4 

32.4 

j Limestone,  4000  lbs . . \ 

49.6 

47.3 

159.7 

\ Kainit,  600  lbs 1 

1 Kainit,  1200  lbs \ 

4 

"j  Aeidulat ’d  bone,  350  lb.  j 

30.3 

33.3 

i Kfnnit  1900  lb«  ^ 

) Steamed  bone,  395  lbs . t 

53.5 

47.6 

164.7 

5 

Potassium  chlorid, 

200  lbs 

31.2 

33.9 

Potassium  chlorid, 
400  lbs. . . . 

48.5 

52.7 

166.3 

6 

Sodium  chlorid,  700  lbs. 

11.1 

13.1 

• None 

24.0 

22.1 

70.3 

7 

Sodium  chlorid,  700  lbs. 

13.3 

14.5 

Kainit,  1200  lbs 

44.5 

47.IT 

8 

Kainit,  600  lbs 

36.8 

37.7 

Kainit,  600  lbs 

44.0 

46.0 

164.5 

9 

Kainit,  300  lbs 

26.4 

25.1 

Kainit,  300  lbs 

41.5 

32.9 

125.9 

10 

None 

14.9' 

14.9 

None 

26.0 

T5X 

69.4 

Estimated  from  1903;  no  yield  was  taken  in  1902  because  of  a misunderstanding. 


'In  1904  the  yields  were  taken  from  quarter-acre  plots  because  of  severe  insect  injury  on 
the  other  parts  of  the  field. 


34 


Soil  Report  No.  9 


[April, 


Reducing  the  application  of  kainit  from  600  to  300  pounds  for  each  two- 
year  period,  reduced  the  yield  of  corn  from  164.5  to  125.9  bushels.  The  two 
applications  of  300  pounds  of  kainit  (Plot  9)  furnished  60  pounds  of  potassium 
for  the  four  years,  an  amount  sufficient  for  84  bushels  of  corn  (grain  and  stalks). 
Attention  is  called  to  the  fact  that  this  is  practically  the  difference  between  the 
yield  of  Plot  9 (125.9  bushels)  and  the  yield  obtained  from  Plot  2 (42.9  bushels), 
the  poorest  untreated  plot. 

Medium  Peat  on  Clay  (1402) 

Medium  peat  on  clay  occurs  in  low,  swampy  areas,  where  the  peat  has  not 
developed  to  a greater  thickness  than  30  inches.  The  total  area  is  640  acres, 
equivalent  to  1 square  mile,  or  .21  percent  of  the  area  of  the  county. 

The  surface,  0 to  6%  inches,  is  a brown  or  black  peat,  the  decomposition 
varying  with  cultivation  and  drainage. 

The  subsurface,  from  6%  inches  to  the  depth  of  the  peat,  is  usually  a 
brownish  peat  that  has  not  undergone  a great  amount  of  decomposition.  In  the 
classification  used  by  this  station,  medium  peat  extends  from  12  to  30  inches  in 
depth,  and  in  most  areas  the  subsurface  is  usually  taken  as  extending  to  the  silty, 
clayey,  or  sandy  layer.  This  gives  a large  variation  in  the  thickness  of  the  sub- 
surface, but  it  is  sampled  to  a depth  of  20  inches. 

The  subsoil  in  this  type  consists  of  a silty  clay  and  almost  invariably  is  of 
light  drab  or  bluish  color,  owing  to  deoxidation  of  iron  by  organic  acids. 

The  treatment  advised  for  this  type  is  the  same  as  for  deep  peat  (1401), 
but  thoro  trials  should  be  made  with  potassium  in  advance  of  extensive  use. 
Drainage  is  an  easier  matter  because  tile  may  usually  be  placed  in  the  clay. 

Medium  Peat  on  Sand  (1402.2) 

Medium  peat  on  sand  is  found  only  on  the  old  beach  of  Lake  Michigan  north 
of  Waukegan,  and  here  in  very  limited  areas  large  enough  to  map.  The  total 
area  is  284  acres. 

The  surface  soil,  0 to  6%  inches,  is  a brownish,  somewhat  decomposed  peat 
mixed  with  more  or  less  sand. 

The  subsurface  extends  to  a depth  of  12  to  20  inches,  passing  into  a drab- 
colored  sand  that  continues  to  an  indefinite  depth.  Practically  none  of  this  is 
under  cultivation,  altho  some  of  it  is  used  for  pasture.  Potassium  is  the  only 
material  suggested  for  trial  applications. 

Shallow  Peat  on  Clay  (1403) 

Shallow  peat  on  clay  occurs  in  small  areas  on  the  upland  and  is  usually 
not  very  uniform.  The  total  area  is  371  acres. 

The  surface  soil,  0 to  6%  inches,  consists  of  a dark,  peaty  material  mixed 
with  more  or  less  sand,  silt,  or  clay.  It  varies  from  pure  peat  to  a very  black 
silt  or  clay  loam.  Very  few  of  these  areas  are  under  cultivation,  but  are  mostly 
in  pasture.  The  tramping  of  cattle  has  produced  hummocks,  which  vary  in 
height  from  4 to  12  inches.  An  illustration  of  these  is  shown. in  Plate  9. 

The  subsurface  soil  is  usually  a brown  silt  loam,  changing  into  a drab  or 
bluish  color  at  12  to  16  inches  in  depth. 


Lake  County 


35 


1915] 

The  subsoil  is  of  the  mottled  drabbish  or  yellowish  color  and  usually  con- 
tains some  fragments  of  limestone.  Alkali  patches  are  of  frequent  occurrence. 

The  first  requirement  of  this  type  is  good  drainage.  Where  the  surface  is 
deficient  in  potassium,  deeper  plowing  will  bring  abundance  of  it  from  the  sub- 
surface to  be  incorporated  with  the  plowed  soil. 

Peaty  Loam  (1410) 

Peaty  loam  is  found  in  small  areas  in  the  depressions  on  the  high  terrace  of 
Lake  Michigan  in  the  northeast  part  of  the  county.  There  is  also  one  larger  area 
in  a broad  valley  west  of  Lake  Bluff.  The  total  area  is  not  large,  amounting  to 
only  2.35  square  miles,  or  .49  percent  of  the  area  of  the  county. 

The  surface  soil,  0 to  6%  inches,  is  a black,  peaty  loam.  The  amount  of 
organic  matter  and  sand  varies  in  different  areas,  the  organic  matter  varying 
from  10  to  25  percent  or  even  more. 

The  subsurface  soil  is  quite  variable.  In  some  areas  it  is  a drabbish  or 
bluish  sand  mixed  with  a variable  amount  of  organic  matter;  in  others  it  is  a 
brown  sandy  loam ; while  in  others  it  is  clayey  or  silty. 

The  subsoil  varies  from  a sand  to  a sand  containing  a considerable  amount 
of  silt  and  clay. 

The  first  requirement  of  this  type  is  good  drainage.  Some  areas  may  re- 
quire the  application  of  potassium  in  order  to  produce  well.  This  is  true  espe- 
cially of  those  areas  where  the  soil  contains  little  or  no  clay.  Alkali  is  frequently 
present  in  sufficient  quantities  to  do  great  injury  to  crops,  more  particularly  to 


Plate  9. — Hummocks  on  “Bog”  Land 


36 


Soil  Refort  No.  9 


[April, 


corn.  The  alkali  consists  chiefly  of  harmless  carbonate  (limestone)  with  smaller 
amounts  of  injurious  magnesium  carbonate. 

In  some  cases  these  peaty  soils  actually  contain  a good  percentage  of  total 
potassium,  more  commonly  in  the  subsurface  or  subsoil  but  sometimes  in  the  sur- 
face soil  also ; and  yet  the  untreated  soil  may  be  unproductive,  while  the  addition 
of  potassium  salts  may  produce  large  and  very  profitable  increases  in  the  yield 
of  corn,  oats,  etc.  In  pot-culture  experiments  we  have  even  been  able  by  the 
addition  of  potassium  sulfate  to  correct  to  a considerable  extent  the  injurious 
property  of  magnesium  carbonate  that  has  been  purposely  applied  to  ordinary 
brown  silt  loam  prairie  soil  known  to  contain  abundance  of  available  potassium. 
These  facts  are  mentioned  here  because  the  Experiment  Station  recom- 
mends, tentatively,  the  application  of  potassium  salt  to  all  classes  of  peaty  and 
alkali  soils  that  are  unproductive  after  being  well  drained,  whenever  the  supply 
of  farm  manure  is  insufficient.  It  should  be  understood  that  plenty  of  farm 
manure,  preferably  quick-acting,  or  readily  decomposable,  manure,  such  as  horse 
manure,  will  supply  potassium  and  thus  accomplish  everything  that  potassium 
salts  can  accomplish;  on  some  swamp  soils  manure  produces  good  results  even 
where  potassium  is  without  effect. 

Black  Mixed  Loam  (1450) 

Black  mixed  loam  occurs  in  many  of  the  low,  swampy  regions  where  organic 
matter  has  not  accumulated  sufficiently  for  the  formation  of  peats.  The  morainal 
areas  contain  large  numbers  of  small  ponds,  in  which  this  type  has  developed, 
but  they  are  too  small  to  be  shown  on  the  map.  The  total  area  of  this  type  is 
19.72  square  miles,  12,622  acres,  or  4.09  percent  of  the  area  of  the  county. 

The  surface  soil,  0 to  6%  inches,  varies  from  a peat  to  a black  clay,  black 
silt,  or  black  sandy  loam.  The  areas  of  these  different  phases  are  so  small,  how- 
ever, and  so  badly  mixed,  that  it  is  practically  impossible  to  make  any  satisfac- 
tory separation  of  them  into  distinct  types.  For  this  reason  the  type  is  called 
black  mixed  loam.  The  content  of  organic  matter  varies  from  6 to  20  percent. 

The  subsurface  soil  varies  to  a less  extent  than  the  surface.  It  is  generally 
a dark  silt  or  clay  loam  with  some  sand  and  gravel  to  a depth  of  14  to  16  inches. 

The  subsoil  varies  from  a drab  to  a yellow  clayey  silty  material  that  is  made 
up  largely  of  boulder  clay.  Many  limestone  gravels  are  found  in  this  stratum. 

On  the  surface  of  this  type  are  found  many  glacial  boulders,  mostly  gran- 
ites, that  have  either  been  left  when  the  other  material  has  been  removed  by 
water,  or  been  brought  to  the  surface  by  the  action  of  frost.  In  many  cases  they 
are  so  numerous  that  cultivation  would  be  impossible  without  removing  them. 
They  vary  in  size  from  a few  inches  to  several  feet  in  diameter. 

In  the  management  of  this  type,  the  first  essential  is  thoro  drainage.  The 
variability  of  the  soil  makes  it  rather  difficult  to  suggest  any  treatment  that  will 
apply  to  the  type  as  a whole.  It  may  be  found  that  some  areas  will  need  applica- 
tions of  potassium.  This  is  true  of  the  small  peaty  areas  as  well  as  the  alkali 
spots  that  are  quite  common  in  the  type.  Comparatively  little  of  this  type  is 
under  cultivation ; nearly  all  of  it  is  either  in  pasture  or  meadow. 

The  tramping  of  stock  on  this  type  produces  hummocks,  or  “bogs,”  as  they 
are  frequently  called  by  the  farmers  of  this  vicinity.  The  height  of  these  may 


1915 ] 


Lake  County 


37 


be  increased  by  freezing  and  thawing  to  12  or  15  inches.  Driving  over  such  an 
area  as  this  with  implements  is  practically  impossible.  A ‘ ‘ bog  cutter,  ’ ’ consist- 
ing of  a series  of  either  straight  or  curved  knives,  is  used  for  reducing  the  hum- 
mocks before  plowing.  (See  Plate  9.) 

Mixed  Loam  ( Bottom  Land ) (1454) 

Mixed  loam  occurs  along  the  streams.  In  many  instances  it  is  very  much 
like  the  black  mixed  loam  (1450) ; as  a rule,  however,  it  has  received  sufficient 
deposit  from  overflow  to  give  it  a more  uniform  character.  The  total  area  of  this 
type  is  8.51  square  miles,  5,446  acres,  or  1.76  percent  of  the  area  of  the  county. 

The  surface  soil,  0 to  6%  inches,  is  brown  to  black  in  color,  varying  in  tex- 
ture from  a silt  loam  to  a sandy  loam.  The  streams  of  this  county  overflow  less 
than  in  other  parts  of  the  state  because  the  numerous  lakes  act  as  reservoirs 
giving  a steady  flow.  The  lakes  also  act  as  silt  basins,  in  which  the  sediment 
settles.  For  these  reasons  there  is  less  sediment  carried  and  deposited  on  the 
flood  plains.  The  amount  of  organic  matter  varies  from  5 to  10  percent  with  an 
average  of  7.7  percent,  or  77  tons  per  acre. 

The  subsurface  soil,  6%  to  20  inches,  varies  from  a brown  silt  loam  to  a 
brown  sandy  loam,  and  is  a little  lighter  in  color  than  the  surface  soil. 

The  subsoil  varies  from  light  brown  to  a yellowish  or  drabbish  color,  indi- 
cating that  sufficient  time  has  elapsed  for  the  formation  of  a distinct  subsoil. 
This  occurs  only  where  sedimentation  takes  place  slowly. 

Because  of  lack  of  drainage,  comparatively  little  of  this  type  is  under  culti- 
vation. It  makes  good  pasture  land,  and  possibly  that  will  be  its  principal  use 
for  years  to  come.  Drainage  is  the  first  thing  necessary.  Where  overflow  occurs, 
high  fertility  is  likely  to  be  maintained. 

Beach  Sand  (1482) 

Beach  sand,  which  might  be  called  mixed  sand  and  peat,  extends  from  Wau- 
kegan to  the  state  line  and  represents  the  beach  of  Lake  Chicago.  Its  greatest 
width  is  about  one  mile.  The  area  consists  of  a large  number  of  sand  ridges  with 
peat  deposits  between  them.  These  ridges  are  usually  but  a few  rods  wide,  and 
still  fewer  rods  apart,  and  the  peat  is  represented  by  such  small  areas  that  it  is 
practically  impossible  to  indicate  them  on  the  map.  The  sand  in  some  places 
has  a covering  of  weeds,  black  oak,  or  stunted  white  pine.  The  soil  is  so  variable 
here  that  it  is  practically  impossible  to  give  a description  of  the  different  strata, 
since  in  many  cases  a rod  either  way  would  mean  an  entire  change  of  type.  If 
drained,  the  treatment  likely  to  be  profitable  will  be  suggested  by  a study  of 
“dune  sand”  and  “deep  peat,”  described  in  the  preceding  pages. 

Lakes 

Lake  county  contains  47  lakes,  having  a total  area  of  18  square  miles,  11,512 
acres,  or  3.72  percent  of  the  entire  area  of  the  county.  Many  of  these  lakes 
have  swampy  shores,  which  fact  indicates  that  a gradual  extinction  is  going  on 
and  that  in  time  they  will  be  filled  with  organic  deposits.  Many  of  the  peaty 
areas  are  without  doubt  extinct  lakes  that  have  been  filled  by  the  accumulation 
of  organic  matter. 


38 


Soil  Report  No.  9 


[April, 


APPENDIX 

A study  of  the  soil  map  and  the  tabular  statements  concerning  crop  require- 
ments, the  plant-food  content  of  the  different  soil  types,  and  the  actual  results 
secured  from  definite  field  trials  with  different  methods  or  systems  of  soil  im- 
provement, and  a careful  study  of  the  discussion  of  general  principles  and  of 
the  descriptions  of  individual  soil  types,  will  furnish  the  most  necessary  and  use- 
ful information  for  the  practical  improvement  and  permanent  preservation  of 
the  productive  power  of  every  kind  of  soil  on  every  farm  in  the  county. 

More  complete  information  concerning  the  most  extensive  and  important  soil 
types  in  the  great  soil  areas  in  all  parts  of  Illinois  is  contained  in  Bulletin  123, 
“The  Fertility  in  Illinois  Soils,”  which  contains  a colored  general  soil-survey 
map  of  the  entire  state. 

Other  publications  of  general  interest  are : 

Bulletin  No.  76,  “Alfalfa  on  Illinois  Soils” 

Bulletin  No.  94,  “Nitrogen  Bacteria  and  Legumes” 

Bulletin  No.  115,  '‘Soil  Improvement  for  the  Worn  Hill  Lands  of  Illinois” 

Bulletin  No.  125,  “Thirty  Years  of  Crop  Rotation  on  the  Common  Prairie  Lands  of 
Illinois  ’ ’ 

Circular  No.  82,  “Physical  Improvement  of  Soils” 

Circular  No.  110,  “Ground  Limestone  for  Acid  Soils” 

Circular  No.  127,  “Shall  We  Use  Natural  Rock  Phosphate  or  Manufactured  Acid  Phos- 
phate for  the  Permanent  Improvement  of  Illinois  Soils?” 

Circular  No.  129,  “The  Use  of  Commercial  Fertilizers” 

Circular  No.  149,  “Results  of  Scientific  Soil  Treatment”  and  “Methods  and  Results  of 
Ten  Years’  Soil  Investigation  in  Illinois” 

Circular  No.  165,  “Shall  We  Use  ‘Complete’  Commercial  Fertilizers  in  the  Corn  Belt?” 
Circular  Nc.  167,  “The  Illinois  System  of  Permanent  Fertility” 

Note. — Information  as  to  where  to  obtain  limestone,  phosphate,  bone  meal,  and  potas- 
sium salts,  methods  of  application,  etc.,  will  also  be  found  in  Circulars  110  and  165. 

Soil  Survey  Methods 

The  detail  soil  survey  of  a county  consists  essentially  of  ascertaining,  and 
indicating  on  a map,  the  location  and  extent  of  the  different  soil  types ; and, 
since  the  value  of  the  survey  depends  upon  its  accuracy,  every  reasonable  means 
is  employed  to  make  it  trustworthy.  To  accomplish  this  object  three  things  are 
essential:  first,  careful,  well-trained  men  to  do  the  work;  second,  an  accurate 
base  map  upon  which  to  show  the  results  of  the  work ; and,  third,  the  means 
necessary  to  enable  the  men  to  place  the  soil-type  boundaries,  streams,  etc., 
accurately  upon  the  map. 

The  men  selected  for  the  work  must  be  able  to  keep  their  location  exactly 
and  to  recognize  the  different  soil  types,  with  their  principal  variations  and  lim- 
its, and  they  must  show  these  upon  the  maps  correctly.  A definite  system  is 
employed  in  checking  up  this  work.  As  an  illustration,  one  soil  expert  will  sur- 
vey and  map  a strip  80  rods  or  160  rods  wide  and  any  convenient  length,  while 
his  associate  will  work  independently  on  another  strip  adjoining  this  area,  and, 
if  the  work  is  correctly  done,  the  soil  type  boundaries  must  match  up  on  the 
line  between  the  two  strips. 

An  accurate  base  map  for  field  use  is  absolutely  necessary  for  soil  mapping. 
The  base  maps  are  made  on  a scale  of  one  inch  to  the  mile.  The  official  data 
of  the  original  or  subsequent  land  survey  are  used  as  a basis  in  the  construc- 
tion of  these  maps,  while  the  most  trustworthy  county  map  available  is  used  in 


1915  J 


Lake  County 


39 


locating  temporarily  the  streams,  roads,  and  railroads.  Since  the  best  of  these 
published  maps  have  some  inaccuracies,  the  location  of  every  road,  stream,  and 
railroad  must  be  verified  by  the  soil  surveyors,  and  corrected  if  wrongly  located. 
In  order  to  make  these  verifications  and  corrections,  each  survey  party  is  pro- 
vided with  an  odometer  for  measuring  distances,  and  a plane  table  for  deter- 
mining directions  of  angling  roads,  railroads,  etc. 

Each  surveyor  is  provided  with  a base  map  of  the  proper  scale,  which  is 
carried  with  him  in  the  field ; and  the  soil-type  boundaries,  ditches,  streams,  and 
necessary  corrections  are  placed  in  their  proper  locations  upon  the  map  while 
the  mapper  is  on  the  area;  Each  section,  or  square  mile,  is  divided  into  40-acre 
plots  on  the  map,  and  the  surveyor  must  inspect  every  ten  acres  and  determine 
the  type  or  types  of  soil  composing  it.  The  different  types  are  indicated  on  the 
map  by  different  colors,  pencils  for  this  purpose  being  carried  in  the  field. 

A small  auger  40  inches  long  forms  for  each  man  an  invaluable  tool  with 
which  he  can  quickly  secure  samples  of  the  different  strata  for  inspection.  An 
extension  for  making  the  auger  80  inches  long  is  carried  by  each  party,  so  that 
any  peculiarity  of  the  deeper  subsoil  layers  may  be  studied.  Each  man  carries 
a compass  to  aid  in  keeping  directions.  Distances  along  roads  are  measured  by 
an  odometer  attached  to  the  axle  of  the  vehicle,  while  distances  in  the  field  off 
the  roads  are  determined  by  pacing,  an  art  in  which  the  men  become  expert  by 
practice.  The  soil  boundaries  can  thus  be  located  with  as  high  a degree  of  ac- 
curacy as  can  be  indicated  by  pencil  on  the  scale  of  one  inch  to  the  mile. 

Soil  Characteristics 

The  unit  in  the  soil  survey  is  the  soil  type,  and  each  type  possesses  more  or 
less  definite  characteristics.  The  line  of  separation  between  adjoining  types  is 
usually  distinct,  but  sometimes  one  type  grades  into  another  so  gradually  that 
it  is  very  difficult  to  draw  the  line  between  them.  In  such  exceptional  cases, 
some  slight  variation  in  the  location  of  soil- type  boundaries  is  unavoidable. 

Several  factors  must  be  taken  into  account  in  establishing  soil  types.  These 
are  (1)  the  geological  origin  of  the  soil,  whether  residual,  glacial,  loessial,  al- 
luvial, colluvial,  or  cumulose;  (2)  the  topography,  or  lay  of  the  land;  (3)  the 
native  vegetation,  as  forest  or  prairie  grasses;  (4)  the  structure,  or  the  depth 
and  character  of  the  surface,  subsurface,  and  subsoil;  (5)  the  physical,  or  me- 
chanical, composition  of  the  different  strata  composing  the  soil,  as  the  percent- 
ages of  gravel,  sand,  silt,  clay,  and  organic  matter  which  they  contain;  (6)  the 
texture,  or  porosity,  granulation,  friability,  plasticity,  etc.;  (7)  the  color  of  the 
strata;  (8)  the  natural  drainage;  (9)  the  agricultural  value,  based  upon  its 
natural  productiveness;  (10)  the  ultimate  chemical  composition  and  reaction. 

The  common  soil  constituents  are  indicated  in  the  following  outline : 

f Organic  ("Comprising  undecomposed  and  partially  decayed 

matter  \ vegetable  or  organic  material 

. .001  mm.1  and  less 
001  mm.  to  .03  mm. 

. .03  mm.  to  1.  mm. 
...  1.  mm.  to  32  mm. 

. . .32.  mm.  and  over 

Further  discussion  of  these  constituents  is  given  in  Circular  82. 


Soil 

constituents 


f Clay . . 

Inorganic  J Sands 

ioESi 


*25  millimeters  equal  1 inch. 


40 


Soil  Report  No.  9 


[April, 


Groups  op  Soil  Types 

The  following  gives  the  different  general  groups  of  soils: 

Peats — Consisting  of  35  percent  or  more  of  organic  matter,  sometimes  mixed 
with  more  or  less  sand  or  silt. 

Peaty  loams — 15  to  35  percent  of  organic  matter  mixed  with  much  sand. 
Some  silt  and  a little  clay  may  be  present. 

Mucks — 15  to  35  percent  of  partly  decomposed  organic  matter  mixed  with 
much  clay  and  silt. 

Clays — Soils  with  more  than  25  percent  of  clay,  usually  mixed  with  much 

silt. 

Clay  loams — Soils  with  from  15  to  25  percent  of  clay,  usually  mixed  with 
much  silt  and  some  sand. 

Silt  loams — Soils  with  more  than  50  percent  of  silt  and  less  than  15  percent 
of  clay,  mixed  with  some  sand. 

Loams — Soils  with  from  30  to  50  percent  of  sand  mixed  with  much  silt  and 
a little  clay. 

Sandy  loams — Soils  with  from  50  to  75  percent  of  sand. 

Fine  sandy  loams — Soils  with  from  50  to  75  percent  of  fine  sand  mixed  with 
much  silt  and  little  clay. 

Sands — Soils  with  more  than  75  percent  of  sand. 

Gravelly  loams — Soils  with  25  to  50  percent  of  gravel  with  much  sand  and 
some  silt. 

Gravels — Soils  with  more  than  50  percent  of  gravel  and  much  sand. 

Stony  loams — Soils  containing  a considerable  number  of  stones  over  one  inch 
in  diameter. 

Rock  outcrop — Usually  ledges  of  rock  having  no  direct  agricultural  value. 

More  or  less  organic  matter  is  found  in  all  the  above  groups. 

Supply  and  Liberation  of  Plant  Food 

The  productive  capacity  of  land  in  humid  sections  depends  almost  wholly 
upon  the  power  of  the  soil  to  feed  the  crop ; and  this,  in  turn,  depends  both 
upon  the  stock  of  plant  food  contained  in  the  soil  and  upon  the  rate  at  which 
it  is  liberated,  or  rendered  soluble  and  available  for  use  in  plant  growth. 
Protection  from  weeds,  insects,  and  fungous  diseases,  tho  exceedingly  important, 
is  not  a positive  but  a negative  factor  in  crop  production. 

The  chemical  analysis  of  the  soil  gives  the  invoice  of  fertility  actually  pres- 
ent in  the  soil  strata  sampled  and  analyzed,  but  the  rate  of  liberation  is  gov- 
erned by  many  factors,  some  of  which  may  be  controlled  by  the  farmer,  while 
others  are  largely  beyond  his  control.  Chief  among  the  important  controllable 
factors  which  influence  the  liberation  of  plant  food  are  limestone  and  decaying 
organic  matter,  which  may  be  added  to  the  soil  by  direct  application  of  ground 
limestone  and  farm  manure.  Organic  matter  may  be  supplied  also  by  green- 
manure  crops  and  crop  residues,  such  as  clover,  cowpeas,  straw,  and  corn  stalks. 
The  rate  of  decay  of  organic  matter  depends  largely  upon  its  age  and  origin, 


1915] 


Lake  County 


41 


and  it  may  be  hastened  by  tillage.  The  chemical  analysis  shows  correctly  the 
total  organic  carbon,  which  represents,  as  a rule,  but  little  more  than  half  the 
organic  matter;  so  that  20,000  pounds  of  organic  carbon  in  the  plowed  soil  of 
an  acre  correspond  to  nearly  20  tons  of  organic  matter.  But  this  organic  mat- 
ter consists  largely  of  the  old  organic  residues  that  have  accumulated  during  the 
past  centuries  because  they  were  resistant  to  decay,  and  2 tons  of  clover  or 
cowpeas  plowed  under  may  have  greater  power  to  liberate  plant  food  than  the 
20  tons  of  old,  inactive  organic  matter.  The  recent  history  of  the  individual 
farm  or  field  must  be  depended  upon  for  information  concerning  recent  addi- 
tions of  active  organic  matter,  whether  in  applications  of  farm  manure,  in 
legume  crops,  or  in  grass-root  sods  of  old  pastures. 

Probably  no  agricultural  fact  is  more  generally  known  by  farmers  and  land- 
owners  than  that  soils  differ  in  productive  power.  Even  tho  plowed  alike  and 
at  the  same  time,  prepared  the  same  way,  planted  the  same  day  with  the  same 
kind  of  seed,  and  cultivated  alike,  watered  by  the  same  rains  and  warmed  by 
the  same  sun,  nevertheless  the  best  acre  may  produce  twice  as  large  a crop  as 
the  poorest  acre  on  the  same  farm,  if  not,  indeed,  in  the  same  field;  and  the 
fact  should  be  repeated  and  emphasized  that  with  the  normal  rainfall  of  Illi- 
nois the  productive  power  of  the  land  depends  primarily  upon  the  stock  of  plant 
food  contained  in  the  soil  and  upon  the  rate  at  which  it  is  liberated,  just  as 
the  success  of  the  merchant  depends  primarily  upon  his  stock  of  goods  and  the 
rapidity  of  sales.  In  both  cases  the  stock  of  any  commodity  must  be  increased 
or  renewed  whenever  the  supply  of  such  commodity  becomes  so  depleted  as  to 
limit  the  success  of  the  business,  whether  on  the  farm  or  in  the  store. 

As  the  organic  matter  decays,  certain  decomposition  products  are  formed, 
including  much  carbonic  acid,  some  nitric  acid,  and  various  organic  acids,  and 
these  have  power  to  act  upon  the  soil  and  dissolve  the  essential  mineral  plant 
foods,  thus  furnishing  soluble  phosphates,  nitrates,  and  other  salts  of  potassium, 
magnesium,  calcium,  etc.,  for  the  use  of  the  growing  crop. 

As  already  explained,  fresh  organic  matter  decomposes  much  more  rapidly 
than  old  humus,  which  represents  the  organic  residues  most  resistant  to  decay 
and  which  consequently  has  accumulated  in  the  soil  during  the  past  centuries. 
The  decay  of  this  old  humus  can  be  hastened  both  by  tillage,  which  maintains 
a porous  condition  and  thus  permits  the  oxygen  of  the  air  to  enter  the  soil  more 
freely  and  to  effect  the  more  rapid  oxidation  of  the  organic  matter,  and  also  by 
incorporating  with  the  old,  resistant  residues  some  fresh  organic  matter,  such 
as  farm  manure,  clover  roots,  etc.,  which  decay  rapidly  and  thus  furnish  or  lib- 
erate organic  matter  and  inorganic  food  for  bacteria,  the  bacteria,  under  such 
favorable  conditions,  appearing  to  have  power  to  attack  and  decompose  the  old 
humus.  It  is  probably  for  this  reason  that  peat,  a very  inactive  and  inefficient 
fertilizer  when  used  by  itself,  becomes  much  more  effective  when  composted  with, 
fresh  farm  manure ; so  that  two  tons  of  the  compost1  may  be  worth  as  much  as 
two  tons  of  manure,  but  if  applied  separately,  the  peat  has  little  value.  Bac- 
terial action  is  also  promoted  by  the  presence  of  limestone. 

“In  his  book,  “Fertilizers,”  published  in  1839,  Cuthbert  W.  Johnson  reported  such  com- 
post to  have  been  much  used  in  England  and  to  be  valued  as  highly,  “weight  for  weight,  as 
farm-yard  dung.” 


42 


Soil  Report  No.  9 


[April, 


The  condition  of  the  organic  matter  of  the  soil  is  indicated  more  or  less 
definitely  by  the  ratio  of  carbon  to  nitrogen.  As  an  average,  the  fresh  organic 
matter  incorporated  with  soils  contains  about  twenty  times  as  much  carbon  as 
nitrogen,  but  the  carbohydrates  ferment  and  decompose  much  more  rapidly  than 
the  nitrogenous  matter ; and  the  old  resistant  organic  residues,  such  as  are  found 
in  normal  subsoils,  commonly  contain  only  five  or  six  times  as  much  carbon  as 
nitrogen.  Soils  of  normal  physical  composition,  such  as  loam,  clay  loam,  silt 
loam,  and  fine  sandy  loam,  when  in  good  productive  condition,  contain  about 
twelve  to  fourteen  times  as  much  carbon  as  nitrogen  in  the  surface  soil;  while 
in  old,  worn  soils  that  are  greatly  in  need  of  fresh,  active,  organic  manures,  the 
ratio  is  narrower,  sometimes  falling  below  ten  of  carbon  to  one  of  nitrogen. 
Soils  of  cut-over  or  burnt-over  timber  lands  sometimes  contain  so  much  partially 
decayed  wood  or  charcoal  as  to  destroy  the  value  of  the  nitrogen-carbon  ratio 
for  the  purpose  indicated.  (Except  in  newly  made  alluvial  soils,  the  ratio  is 
usually  narrower  in  the  subsurface  and  subsoil  than  in  the  surface  stratum.) 

It  should  be  kept  in  mind  that  crops  are  not  made  out  of  nothing.  They 
are  composed  of  ten  different  elements  of  plant  food,  every  one  of  which  is 
absolutely  essential  for  the  growth  and  formation  of  every  agricultural  plant. 
Of  these  ten  elements  of  plant  food,  only  two  (carbon  and  oxygen)  are  secured 
from  the  air  by  all  agricultural  plants,  only  one  (hydrogen)  from  water,  and 
seven  from  the  soil.  Nitrogen,  one  of'  these  seven  elements  secured  from  the 
soil  by  all  plants,  may  also  be  secured  from  the  air  by  one  class  of  plants 
(legumes),  in  case  the  amount  liberated  from  the  soil  is  insufficient;  but  even 
these  plants  (which  include  only  the  clovers,  peas,  beans,  and  vetches,  among 
our  common  agricultural  plants)  secure  from  the  soil  alone  six  elements  (phos- 
phorus, potassium,  magnesium,  calcium,  iron,  and  sulfur),  and  also  utilize  the 
soil  nitrogen  so  far  as  it  becomes  soluble  and  available  during  their  period  of 
growth. 

Plants  are  made  of  plant-food  elements  in  just  the  same  sense  that  a build- 
ing is  made  of  wood  and  iron,  brick,  stone,  and  mortar.  Without  materials, 
nothing  material  can  be  made.  The  normal  temperature,  sunshine,  rainfall,  and 
length  of  season  in  central  Illinois  are  sufficient  to  produce  50  bushels  of  wheat 
per  acre,  100  bushels  of  corn,  100  bushels  of  oats,  and  4 tons  of  clover  hay;  and, 
where  the  land  is  properly  drained  and  properly  tilled,  such  crops  would  fre- 
quently be  secured  if  the  plant  foods  were  present  in  sufficient  amounts  and 
liberated  at  a sufficiently  rapid  rate  to  meet  the  absolute  needs  of  the  crops. 

Crop  Requirements 

The  accompanying  table  shows  the  requirements  of  wheat,  corn,  oats,  and 
clover  for  the  five  most  important  plant-food  elements  which  the  soil  must  fur- 
nish. (Iron  and  sulfur  are  supplied  normally  in  sufficient  abundance  compared 
with  the  amounts  needed  by  plants,  so  that  they  are  never  known  to  limit  the 
ffield  of  general  farm  crops  grown  under  normal  conditions.) 


1915 ] 


Lake  County 


43 


Table  A. — Plant  Pood  in  Wheat,  Corn,  Oats,  and  Clover 


Produce 

Nitro- 

Phos- 

Potas- 

Magne- 

Cal- 

Kind 

Amount 

gen 

phorus 

sium 

sium 

cium 

lbs. 

lbs. 

lbs. 

lbs. 

lbs. 

Wheat,  grain 

50  bu. 

71 

12 

13 

4 

1 

Wheat  straw 

2%  tons 

25 

4 

45 

4 

10 

Corn,  grain 

100  bu. 

100 

17 

19 

7 

1 

Corn  stover 

3 tons 

48 

6 

52 

10 

21 

Corn  cobs 

% ton 

2 

2 

Oats,  grain 

100  bu. 

66 

11 

16 

4 

2 

Oat  straw 

2%  tons 

31 

5 

52 

7 

15 

Clover  seed 

4 bu. 

7 

2 

3 

1 

1 

Clover  hay 

4 tons 

160 

20 

120 

31 

117 

Total  in  grain  and  seed 

2441 

42 

51 

16 

4 

Total  in  four  crops.. 

5101 

77 

322 

68 

168 

JThcse  amounts  include  the  nitrogen  contained  in  the  clover  seed  or  hay,  which,  how- 
ever, may  be  secured  from  the  air. 


To  be  sure,  these  are  large  yields,  but  shall  we  try  to  make  possible  the 
production  of  yields  only  half  or  a quarter  as  large  as  these,  or  shall  we  set  as 
our  ideal  this  higher  mark,  and  then  approach  it  as  nearly  as  possible  with 
profit?  Among  the  four  crops,  corn  is  the  largest,  with  a total  yield  of  more 
than  six  tons  per  acre;  and  yet  the  100-bushel  crop  of  corn  is  often  produced 
on  rich  pieces  of  land  in  good  seasons.  In  very  practical  and  profitable  systems 
of  farming,  the  Illinois  Experiment  Station  has  produced,  as  an  average  of  the 
six  years  1905  to  1910,  a yield  of  87  bushels  of  corn  per  acre  in  grain  farming 
(with  limestone  and  phosphorus  applied,  and  with  crop  residues  and  legume 
crops  turned  under),  and  90  bushels  per  acre  in  live-stock  farming  (with  lime- 
stone, phosphorus,  and  manure). 

The  importance  of  maintaining  a rich  surface  soil  cannot  be  too  strongly 
emphasized.  This  is  well  illustrated  by  data  from  the  Rothamsted  Experiment 
Station,  the  oldest  in  the  world.  On  Broadbalk  field,  where  wheat  has  been 
grown  since  1844,  the  average  yields  for  the  ten  years  1892  to  1901  were  12.3 
bushels  per  acre  on  Plot  3 (unfertilized)  and  31.8  bushels  on  Plot  7 (well  ferti- 
lized), but  the  amounts  of  both  nitrogen  and  phosphorus  in  the  subsoil  (9  to  27 
inches)  were  distinctly  greater  in  Plot  3 than  in  Plot  7,  thus  showing  that  the 
higher  yields  from  Plot  7 were  due  to  the  fact  that  the  plowed  soil  had  been 
enriched.  In  1893  Plot  7 contained  per  acre  in  the  surface  soil  (0  to  9 inches) 
about  600  pounds  more  nitrogen  and  900  pounds  more  phosphorus  than  Plot  3. 
Even  a rich  subsoil  has  little  value  if  it  lies  beneath  a worn-out  surface. 

Methods  of  Liberating  Plant  Food 

Limestone  and  decaying  organic  matter  are  the  principal  materials  which 
the  farmer  can  utilize  most  profitably  to  bring  about  the  liberation  of  plant 
food.  The  limestone  corrects  the  acidity  of  the  soil  and  thus  encourages  the 
development  not  only  of  the  nitrogen-gathering  bacteria  which  live  in  the  nodules 
on  the  roots  of  clover,  cowpeas,  and  other  legumes,  but  also  the  nitrifying 
bacteria,  which  have  power  to  transform  the  insoluble  and  unavailable  organic 


44 


Soil  Report  No.  9 


[April, 


nitrogen  into  soluble  and  available  nitrate  nitrogen.  At  the  same  time,  the 
products  of  this  decomposition  have  power  to  dissolve  the  minerals  contained 
in  the  soil,  such  as  potassium  and  magnesium,  and  also  to  dissolve  the  insoluble 
phosphate  and  limestone  which  may  be  applied  in  low-priced  forms. 

Tillage,  or  cultivation,  also  hastens  the  liberation  of  plant  food  by  permit- 
ting the  air  to  enter  the  soil  and  burn  out  the  organic  matter;  but  it  should 
never  be  forgotten  that  tillage  is  wholly  destructive,  that  it  adds  nothing  what- 
ever to  the  soil,  but  always  leaves  it  poorer.  Tillage  should  be  practiced  so 
far  as  is  necessary  to  prepare  a suitable  seed  bed  for  root  development  and 
also  for  the  purpose  of  killing  weeds,  but  more  than  this  is  unnecessary  and 
unprofitable  in  seasons  of  normal  rainfall ; and  it  is  much  better  actually  to 
enrich  the  soil  by  proper  applications  or  additions,  including  limestone  and 
organic  matter  (both  of  which  have  power  to  improve  the  physical  condition 
as  well  as  to  liberate  plant  food)  than  merely  to  hasten  soil  depletion  by  means 
of  excessive  cultivation. 


Permanent  Soil  Improvement 

The  best  and  most  profitable  methods  for  the  permanent  improvement  of 
the  common  soils  of  Illinois  are  as  follows: 

(1)  If  the  soil  is  acid,  apply  at  least  two  tons  per  acre  of  ground  lime- 
stone, preferably  at  times  magnesian  limestone  (CaC03MgC03),  which  con- 
tains both  calcium  and  magnesium  and  has  slightly  greater  power  to  correct 
soil  acidity,  ton  for  ton,  than  the  ordinary  calcium  limestone  (CaC03) ; and 
continue  to  apply  about  two  tons  per  acre  of  ground  limestone  every  four  or 
five  years.  On  strongly  acid  soils,  or  on  land  being  prepared  for  alfalfa,  five 
tons  per  acre  of  ground  limestone  may  well  be  used  for  the  first  application. 

(2)  Adopt  a good  rotation  of  crops,  including  a liberal  use  of  legumes,  and 
increase  the  organic  matter  of  the  soil  either  by  plowing  under  the  legume  crops 
and  other  crop  residues  (straw  and  corn  stalks),  or  by  using  for  feed  and  bed- 
ding practically  all  the  crops  raised  and  returning  the  manure  to  the  land  with 
the  least  possible  loss.  No  one  can  say  in  advance  what  will  prove  to  be  the 
best  rotation  of  crops,  because  of  variation  in  farms  and  farmers,  and  in  prices 
for  produce,  but  the  following  are  suggested  to  serve  as  models  or  outlines: 

First  year,  corn. 

Second  year,  corn. 

Third  year,  wheat  or  oats  (with  clover  or  clover  and  grass). 

Fourth  year,  clover  or  clover  and  grass. 

Fifth  year,  wheat  and  clover  or  grass  and  clover. 

Sixth  year,  clover  or  clover  and  grass. 

Of  course  there  should  be  as  many  fields  as  there  are  years  in  the  rotation. 
In  grain  farming,  with  small  grain  grown  the  third  and  fifth  years,  most  of  the 
coarse  products  should  be  returned  to  the  soil,  and  the  clover  may  be  clipped 
and  left  on  the  land  (only  the  clover  seed  being  sold  the  fourth  and  sixth  years)  ; 
or,  in  live-stock  farming,  the  field  may  be  used  three  years  for  timothy  and 
clover  pasture  and  meadow  if  desiS&d.  The  system  may  be  reduced  to  a five- 
year  rotation  by  cutting  out  either  the  second  or  the  sixth  year,  and  to  a four- 
year  system  by  omitting  the  fifth  and  sixth  years. 


1915] 


Lake  County 


45 


With  two  years  of  corn,  followed  by  oats  with  clover-seeding  the  third  year, 
and  by  clover  the  fourth  year,  all  produce  can  be  used  for  feed  and  bedding  if 
other  land  is  available  for  permanent  pasture.  Alfalfa  may  be  grown  on  a fifth 
field  for  four  or  eight  years,  which  is  to  be  alternated  with  one  of  the  four;  or 
the  alfalfa  may  be  moved  every  five  years,  and  thus  rotated  over  all  five  fields 
every  twenty-five  years. 

Other  four-year  rotations  more  suitable  for  grain  farming  are : 

Wheat  (and  clover),  corn,  oats,  and  clover;  or  corn  (and  clover),  cowpeas,  wheat,  and 
clover.  (Alfalfa  may  be  grown  on  a fifth  field  and  rotated  every  five  years,  the 
hay  being  sold.) 

Good  three-year  rotations  are: 

Corn,  oats,  and  clover;  corn,  wheat,  and  clover;  or  wheat  (and  clover),  corn  (and 
clover) , and  cowpeas,  in  which  two  cover  crops  and  one  regular  crop  of  legumes 
are  grown  in  three  years. 

A five-year  rotation  of  (1)  corn  (and  clover),  (2)  cowpeas,  (3)  wheat, 
(4)  clover,  and  (5)  wheat  (and  clover)  allows  legumes  to  be  seeded  four  times. 
Alfalfa  may  be  grown  on  a sixth  field  for  five  or  six  years  in  the  combination, 
rotation,  alternating  between  two  fields  every  five  years,  or  rotating  over  all  the 
fields  if  moved  every  six  years. 

To  avoid  clover  sickness  it  may  sometimes  be  necessary  to  substitute  sweet 
clover  or  alsike  for  red  clover  in  about  every  third  rotation,  and  at  the  same 
time  to  discontinue  its  use  in  the  cover-crop  mixture.  If  the  corn  crop  is  not 
too  rank,  cowpeas  or  soybeans  may  also  be  used  as  a cover  crop  (seeded  at  the 
last  cultivation)  in  the  southern  part  of  the  state,  and,  if  necessary  to  avoid 
disease,  these  may  well  alternate  in  successive  rotations. 

For  easy  figuring  it  may  well  be  kept  in  mind  that  the  following  amounts 
of  nitrogen  are  required  for  the  produce  named : 

1 bushel  of  oats  (grain  and  straw)  requires  1 pound  of  nitrogen. 

1 bushel  of  corn  (grain  and  stalks)  requires  1%  pounds  of  nitrogen. 

1 bushel  of  wheat  (grain  and  straw)  requires  2 pounds  of  nitrogen. 

1 ton  of  timothy  requires  24  pounds  of  nitrogen. 

1 ton  of  clover  contains  40  pounds  of  nitrogen. 

1 ton  of  cowpeas  contains  43  pounds  of  nitrogen. 

1 ton  of  average  manure  contains  10  pounds  of  nitrogen. 

The  roots  of  clover  contain  about  half  as  much  nitrogen  as  the  tops,  and 
the  roots  of  cowpeas  contain  about  one-tenth  as  much  as  the  tops. 

Soils  of  moderate  productive  power  will  furnish  as  much  nitrogen  to  clover 
(and  two  or  three  times  as  much  to  cowpeas)  as  will  be  left  in  the  roots  and 
stubble.  In  grain  crops,  such  as  wheat,  corn,  and  oats,  about  two-thirds  of  the 
nitrogen  is  contained  in  the  grain  and  one-third  in  the  straw  or  stalks.  (See 
also  discussion  of  “The  Potassium  Problem,”  on  pages  following.) 

(3)  On  all  lands  deficient  in  phosphorus  (except  on  those  susceptible  to 
serious  erosion  by  surface  washing  or  gullying)  apply  that  element  in  consid- 
erably larger  amounts  than  are  required  to  meet  the  actual  needs  of  the  crops 
desired  to  be  produced.  The  abundant  information  thus  far  secured  shows  posi- 
tively that  fine-ground  natural  rock  phospmfte  can  be  used  successfully  and  very 
profitably,  and  clearly  indicates  that  this  material  will  be  the  most  economical 
form  of  phosphorus  to  use  in  all  ordinary  systems  of  permanent,  profitable  soil 


46 


Soil  Report  No.  9 


[Aprn, 


improvement.  The  first  application  may  well  be  one  ton  per  acre,  and  subse- 
quently about  one-half  ton  per  acre  every  four  or  five  years  should  be  applied, 
at  least  until  the  phosphorus  content  of  the  plowed  soil  reaches  2,000  pounds  per 
acre,  which  may  require  a total  application  of  from  three  to  five  or  six  tons  per 
acre  of  raw  phosphate  containing  121/2  percent  of  the  element  phosphorus. 

Steamed  bone  meal  and  even  acid  phosphate  may  be  used  in  emergencies, 
but  it  should  always  be  kept  in  mind  that  phosphorus  delivered  in  Illinois  costs 
about  3 cents  a pound  in  raw  phosphate  (direct  from  the  mine  in  carload  lots), 
but  10  cents  a pound  in  steamed  bone  meal,  and  about  12  cents  a pound  in  acid 
phosphate,  both  of  which  cost  too  much  per  ton  to  permit  their  common  purchase 
by  farmers  in  carload  lots,  which  is  not  the  case  with  limestone  or  raw  phos- 
phate. 

Phosphorus  once  applied  to  the  soil  remains  in  it  until  removed  in  crops, 
unless  carried  away  mechanically  by  soil  erosion.  (The  loss  by  leaching  is  only 
about  1^/2  pounds  per  acre  per  annum,  so  that  more  than  150  years  would  be 
required  to  leach  away  the  phosphorus  applied  in  one  ton  of  raw  phosphate.) 

The  phosphate  and  limestone  may  be  applied  at  any  time  during  the  rota- 
tion, but  a good  method  is  to  apply  the  limestone  after  plowing  and  work  it  into 
the  surface  soil  in  preparing  the  seed  bed  for  wheat,  oats,  rye,  or  barley,  where 
clover  is  to  be  seeded ; while  phosphate  is  best  plowed  under  with  farm  manure, 
clover,  or  other  green  manures,  which  serve  to  liberate  the  phosphorus. 

(4)  Until  the  supply  .of  decaying  organic  matter  has  been  made  adequate, 
on  the  poorer  types  of  upland  timber  and  gray  prairie  soils  some  temporary 
benefit  may  be  derived  from  the  use  of  a soluble  salt  or  a mixture  of  salts,  such 
as  kainit,  which  contains  both  potassium  and  magnesium  in  soluble  form  and 
also  some  common  salt  (sodium  chlorid).  About  600  pounds  per  acre  of  kainit 
applied  and  turned  under  with  the  raw  phosphate  will  help  to  dissolve  the  phos- 
phorus as  well  as  to  furnish  available  potassium  and  magnesium,  and  for  a few 
years  such  use  of  kainit  may  be  profitable  on  lands  deficient  in  organic  matter, 
but  the  evidence  thus  far  secured  indicates  that  its  use  is  not  absolutely  necessary 
and  that  it  will  not  be  profitable  after  adequate  provision  is  made  for  supplying 
decaying  organic  matter,  since  this  will  necessitate  returning  to  the  soil  the 
potassium  contained  in  the  crop  residues  from  grain  farming  or  the  manure 
produced  in  live-stock  farming,  and  will  also  provide  for  the  liberating  of  potas- 
sium from  the  soil.  (Where  hay  or  straw  is  sold,  manure  should  be  bought.) 

On  soils  which  are  subject  to  surface  washing,  including  especially  the 
yellow  silt  loam  of  the  upland  timber  area,  and  to  some  extent  the  yellow-gray 
silt  loam  and  other  more  rolling  areas,  the  supply  of  minerals  in  the  subsurface 
and  subsoil  (which  gradually  renew  the  surface  soil)  tends  to  provide  for  a 
low-grade  system  of  permanent  agriculture  if  some  use  is  made  of  legume  plants, 
as  in  long  rotations  with  much  pasture,  because  both  the  minerals  and  nitrogen 
are  thus  provided  in  some  amount  almost  permanently ; but  where  such  lands 
are  farmed  under  such  a system,  not  more  than  two  or  three  grain  crops  should 
be  grown  during  a period  of  ten  or  twelve  years,  the  land  being  kept  in  pasture 
most  of  the  time;  and  where  the  soil  is  acid  a liberal  use  of  limestone,  as  top- 
dressings  if  necessary,  and  occasional  reseeding  with  clovers  will  benefit  both  the 
pasture  and  indirectly  the  grain  crops. 


1915] 


Lake  County 


47 


Advantage  of  Crop  Rotation  and  Permanent  Systems 

It  should  be  noted  that  clover  is  not  likely  to  be  well  infected  with  the 
clover  bacteria  during  the  first  rotation  on  a given  farm  or  field  where  it  has 
not  been  grown  before  within  recent  years ; but  even  a partial  stand  of  clover 
the  first  time  will  probably  provide  a thousand  times  as  many  bacteria  for  the 
next  clover  crop  as  one  could  afford  to  apply  in  artificial  inoculation,  for  a single 
root-tubercle  may  contain  a million  bacteria  developed  from  one  during  the  sea- 
son’s growth. 

This  is  only  one  of  several  advantages  of  the  second  course  of  the  rotation 
over  the  first  course.  Thus  the  mere  practice  of  crop  rotation  is  an  advantage, 
especially  in  helping  to  rid  the  land  of  insects  and  foul  grass  and  weeds.  The 
clover  crop  is  an  advantage  to  subsequent  crops  because  of  its  deep-rooting  char- 
acteristic. The  larger  applications  of  organic  manures  (made  possible  by  the 
larger  crops)  are  a great  advantage ; and  in  systems  of  permanent  soil  improve- 
ment, such  as  are  here  advised  and  illustrated,  more  limestone  and  more  phos- 
phorus are  provided  than  are  needed  for  the  meager  or  moderate  crops  pro- 
duced during  the  first  rotation,  and  consequently  the  crops  in  the  second  rota- 
tion have  the  advantage  of  such  accumulated  residues  (well  incorporated  with 
the  plowed  soil)  in  addition  to  the  regular  applications  made  during  the  second 
rotation. 

This  means  that  these  systems  tend  positively  toward  the  making  of  richer 
lands.  The  ultimate  analyses  recorded  in  the  tables  give  the  absolute  invoice 
of  these  Illinois  soils.  They  show  that  most  of  them  are  positively  deficient  only 
in  limestone,  phosphorus,  and  nitrogenous  organic  matter ; and  the  accumulated 
information  from  careful  and  long-continued  investigations  in  different  parts  of 
the  United  States  clearly  establishes  the  fact  that  in  general  farming  these  essen- 
tials can  be  supplied  with  greatest  economy  and  profit  by  the  use  of  ground  nat- 
ural limestone,  very  finely  ground  natural  rock  phosphate,  and  legume  crops  to 
be  plowed  under  directly  or  in  farm  manure.  On  normal  soils  no  other  applica- 
tions are  absolutely  necessary,  but,  as  already  explained,  the  addition  of  some 
soluble  salt  in  the  beginning  of  a system  of  improvement  on  some  of  these  soils 
produces  temporary  benefit,  and  if  some  inexpensive  salt,  such  as  kainit,  is  used, 
it  may  produce  sufficient  increase  to  more  than  pay  the  added  cost. 

The  Potassium  Problem 

As  reported  in  Illinois  Bulletin  123,  where  wheat  has  been  grown  every  year 
for  moi’e  than  half  a century  at  Rothamsted,  England,  exactly  the  same  increase 
was  produced  (5.6  bushels  per  acre),  as  an  average  of  the  first  24  years,  whether 
potassium,  magnesium,  or  sodium  was  applied,  the  rate  of  application  per  annum 
being  200  pounds  of  potassium  sulfate  and  molecular  equivalents  of  magnesium 
sulfate  and  sodium  sulfate.  As  an  average  of  60  years  (1852  to  1911),  the  yield 
of  wheat  was  12.7  bushels  on  untreated  land  and  23.3  bushels  where  86  pounds 
of  nitrogen  and  29  pounds  of  phosphorus  per  acre  per  annum  were  applied. 
As  further  additions,  85  pounds  of  potassium  raised  the  yield  to  31.3  bushels; 
52  pounds  of  magnesium  raised  it  to  29.2  bushels ; and  50  pounds  of  sodium  raised 
it  to  29.5  bushels.  Where  potassium  was  applied,  the  wheat  crop  removed  an- 


48 


Soil  Report  No.  9 


[April, 


nually  an  average  of  40  pounds  of  that  element  in  the  grain  and  straw,  or  three 
times  as  much  as  would  be  removed  in  the  grain  only  for  such  crops  as  are 
suggested  in  Table  A.  The  Rothamsted  soil  contained  an  abundance  of  lime- 
stone, but  no  organic  matter  was  provided,  except  the  little  in  the  stubble  and 
roots  of  the  wheat  plants. 

On  another  field  at  Rothamsted  the  average  yield  of  barley  for  60  years 
(1852  to  1911)  was  14.2  bushels  on  untreated  land,  38.1  bushels  where  43  pounds 
of  nitrogen  and  29  pounds  of  phosphorus  were  applied  per  acre  per  annum; 
while  the  further  addition  of  85  pounds  of  potassium,  19  pounds  of  magnesium, 
and  14  pounds  of  sodium  (all  in  sulfates)  raised  the  average  yield  to  41.5 
bushels.  Where  only  70  pounds  of  sodium  were  applied  in  addition  to  the 
nitrogen  and  phosphorus,  the  average  was  43.0  bushels.  Thus,  as  an  average 
of  60  years,  the  use  of  sodium  produced  1.8  bushels  less  wheat  and  1.5  bushels 
more  barley  than  the  use  of  potassium,  with  both  grain  and  straw  removed  and 
no  organic  manures  returned. 

In  recent  years  the  effect  of  .potassium  is  becoming  much  more  marked  than 
that  of  sodium  or  magnesium,  on  the  wheat  crop ; but  this  must  be  expected  to 
occur  in  time  where  no  potassium  is  returned  in  straw  or  manure,  and  no  pro- 
vision made  for  liberating  potassium  from  the  supply  still  remaining  in  the  soil. 
If  the  wheat  straw,  which  contains  more  than  three-fourths  of  the  potassium 
removed  in  the  wheat  crop  (see  Table  A),  were  returned  to  the  soil,  the  neces- 
sity of  purchasing  potassium  in  a good  system  of  farming  on  such  land  would 
be  at  least  very  remote,  for  the  supply  would  be  adequately  maintained  by 
the  actual  amount  returned  in  the  straw,  together  with  the  additional  amount 
which  would  be  liberated  from  the  soil  by  the  action  of  decomposition  products. 

While  about  half  the  potassium,  nitrogen,  and  organic  matter,  and  about 
One-fourth  the  phosphorus  contained  in  manure  is  lost  by  three  or  four  months  ’ 
exposure  in  the  ordinary  pile  in  the  barn  yard,  there  is  practically  no  loss 
if  plenty  of  absorbent  bedding  is  used  on  cement  floors,  and  if  the  manure  is 
hauled  to  the  field  and  spread  within  a day  or  two  after  it  is  produced.  Again, 
while  in  average  live-stock  farming  the  animals  destroy  two-thirds  of  the  or- 
ganic matter  and  retain  one-fourth  of  the  nitrogen  and  phosphorus  from  the 
food  they  consume,  they  retain  less  than  one-tenth  of  the  potassium ; so  that  the 
actual  loss  of  potassium  in  the  products  sold  from  the  farm,  either  in  grain 
farming  or  in  live-stock  farming,  is  wholly  negligible  on  land  containing  25,000 
pounds  or  more  of  potassium  in  the  surface  6%  inches. 

The  removal  of  one  inch  of  soil  per  century  by  surface  washing  (which  is 
likely  to  occur  wherever  there  is  satisfactory  surface  drainage  and  frequent  cul- 
tivation) will  permanently  maintain  the  potassium  in  grain  farming  by  re- 
newal from  the  subsoil,  provided  one-third  of  the  potassium  is  removed  by  crop- 
ping before  the  soil  is  carried  away. 

From  all  these  facts  it  will  be  seen  that  the  potassium  problem  is  not  one 
of  addition  but  of  liberation ; and  the  Rothamsted  records  show  that  for  many 
years  other  soluble  salts  have  practically  the  same  power  as  potassium  to  increase 
crop  yields  in  the  absence  of  sufficient  decaying  organic  matter.  Whether  this 


1915] 


Lake  County 


49 


action  relates  to  supplying  or  liberating  potassium  for  its  own  sake,  or  to  the 
power  of  the  soluble  salt  to  increase  the  availability  of  phosphorus  or  other  ele- 
ments, is  not  known,  but  where  much  potassium  is  removed,  as  in  the  entire  crops 
at  Rothamsted,  with  no  return  of  organic  residues,  probably  the  soluble  salt 
functions  in  both  ways. 

As  an  average  of  112  separate  tests  conducted  in  1907,  1908,  1909,  and  1910 
on  the  Fairfield  experiment  field,  an  application  of  200  pounds  of  potassium 
sulfate,  containing  85  pounds  of  potassium  and  costing  $5.10,  increased  the  yield 
of  corn  by  9.3  bushels  per  acre ; while  600  pounds  of  kainit,  containing  only  60 
pounds  of  potassium  and  costing  $4,  gave  an  increase  of  10.7  bushels.  Thus,  at 
40  cents  a bushel  for  corn,  the  kainit  paid  for  itself ; but  these  results,  like  those 
at  Rothamsted,  were  secured  where  no  adequate  provision  had  been  made  for 
decaying  organic  matter. 

Additional  experiments  at  Fairfield  included  an  equally  complete  test  with 
potassium  sulfate  and  kainit  on  land  to  which  8 tons  per  acre  of  farm  manure 
were  applied.  As  an  average  of  112  tests  with  each  material,  the  200  pounds 
of  potassium  sulfate  increased  the  yield  of  corn  by  1.7  bushels,  while  the  600 
pounds  of  kainit  also  gave  an  increase  of  1.7  bushels.  Thus,  where  organic 
manure  was  supplied,  very  little  effect  was  produced  by  the  addition  of  either1 
potassium  sulfate  or  kainit ; in  part  perhaps  because  the  potassium  removed  in 
the  crops  is  mostly  returned  in  the  manure  if  properly  cared  for,  and  perhaps 
in  larger  part  because  the  decaying  organic  matter  helps  to  liberate  and  hold 
in  solution  other  plant-food  elements,  especially  phosphorus. 

In  laboratory  experiments  at  the  Illinois  Experiment  Station,  it  has  been 
shown  by  chemical  analysis  that  potassium  salts  and  most  other  soluble  salts 
increase  the  solubility  of  the  phosphorus  in  soil  and  in  rock  phosphate;  also 
that  the  addition  of  glucose  with  rock  phosphate  in  pot-culture  experiments 
increases  the  availability  of  the  phosphorus,  as  measured  by  plant  growth,  altho 
the  glucose  consists  only  of  carbon,  hydrogen,  and  oxygen,  and  thus  contains 
no  plant  food  of  value. 

If  we  remember  that,  as  an  average,  live  stock  destroy  two-thirds  of  the  or- 
ganic matter  of  the  food  they  consume,  it  it  easy  to  determine  from  Table  A that 
more  organic  matter  will  be  supplied  in  a proper  grain  system  than  in  a strictly 
live-stock  system ; and  the  evidence  thus  far  secured  from  older  experiments  at 
the  University  and  at  other  places  in  the  state  indicates  that  if  the  corn  stalks, 
straw,  clover,  etc.,  are  incorporated  with  the  soil  as  soon  as  practicable  after  they 
are  produced  (which  can  usually  be  done  in  the  late  fall  or  early  spring),  there 
is  little  or  no  difficulty  in  securing  sufficient  decomposition  in  our  humid  climate 
to  avoid  serious  interference  with  the  capillary  movement  of  the  soil  moisture, 
a common  danger  from  plowing  under  too  much  coarse  manure  of  any  kind  in 
the  late  spring  of  a dry  year. 

If,  however,  the  entire  produce  of  the  land  is  sold  from  the  farm,  as  in  hay 
farming  or  when  both  grain  and  straw  are  sold,  of  course  the  draft  on  potas- 
sium will  then  be  so  great  that  in  time  it  must  be  renewed  by  some  sort  of  appli- 
cation. As  a rule,  farmers  following  this  practice  ought  to  secure  manure  from 
town,  since  they  furnish  the  bulk  of  the  material  out  of  which  manure  is  pro- 
duced. 


so 


Soil  Report  No.  9 


[April, 


Calcium  and  Magnesium 

When  measured  by  the  actual  crop  requirements  for  plant  food,  magnesium 
and  calcium  are  more  limited  in  some  Illinois  soils  than  potassium.  But  with 
these  elements  we  must  also  consider  the  loss  by  leaching.  As  an  average  of  90 
analyses1  of  Illinois  well-waters  drawn  chiefly  from  glacial  sands,  gravels,  or  till, 
3 million  pounds  of  water  (about  the  average  annual  drainage  per  acre  for 
Illinois)  contained  11  pounds  of  potassium,  130  of  magnesium,  and  330  of  cal- 
cium. These  figures  are  very  significant,  and  it  may  be  stated  that  if  the  plowed 
soil  is  well  supplied  with  the  carbonates  of  magnesium  and  calcium,  then  a very 
considerable  proportion  of  these  amounts  will  be  leached  from  that  stratum. 
Thus  the  loss  of  calcium  from  the  plowed  soil  of  an  acre  at  Rothamsted,  England, 
where  the  soil  contains  plenty  of  limestone,  has  averaged  more  than  300  pounds 
a year  as  determined  by  analyzing  the  soil  in  1865  and  again  in  1905.  Prac- 
tically the  same  amount  of  calcium  was  found,  by  analyses,  in  the  Rothamsted 
drainage  waters. 

Common  limestone,  which  is  calcium  carbonate  (CaC03),  contains,  when 
pure,  40  percent  of  calcium,  so  that  800  pounds  of  limestone  are  equivalent  to 
320  pounds  of  calcium.  Where  10  tons  per  acre  of  ground  limestone  were 
applied  at  Edgewood,  Illinois,  the  average  annual  loss  during  the  next  ten  years 
amounted  to  790  pounds  per  acre.  The  definite  data  from  careful  investigations 
seem  to  be  ample  to  justify  the  conclusion  that  where  limestone  is  needed  at 
least  2 tons  per  acre  should  be  applied  every  4 or  5 years. 

It  is  of  interest  to  note  that  thirty  crops  of  clover  of  four  tons  each  would 
require  3,510  pounds  of  calcium,  while  the  most  common  prairie  land  of  southern 
Illinois  contains  only  3,420  pounds  of  total  calcium  in  the  plowed  soil  of  an 
acre.  (See  Soil  Report  No.  1.)  Thus  limestone  has  a positive  value  on  some 
soils  for  the  plant  food  which  it  supplies,  in  addition  to  its  value  in  correcting 
soil  acidity  and  in  improving  the  physical  condition  of  the  soil.  Ordinary  lime- 
stone (abundant  in  the  southern  and  western  parts  of  the  state)  contains  nearly 
800  pounds  of  calcium  per  ton;  while  a good  grade  of  dolomitic  limestone  (the 
more  common  limestone  of  northern  Illinois)  contains  about  400  pounds  of  cal- 
cium and  300  pounds  of  magnesium  per  ton.  Both  of  these  elements  are  fur- 
nished in  readily  available  form  in  ground  dolomitic  limestone. 

Physical  Improvement  of  Soils 

In  the  management  of  most  soil  types,  one  very  important  thing,  aside  from 
proper  fertilization,  tillage,  and  drainage,  is  to  keep  the  soil  in . good  physical 
condition,  or  good  tilth.  The  constituent  most  important  for  this  purpose  is 
organic  matter.  Not  only  does  it  impart  good  tilth  to  the  soil,  but  it  prevents 
much  loss  by  washing  on  rolling  land,  warms  the  soil  by  absorption  of  heat,  re- 
tains moisture  during  drouth,  furnishes  nitrogen  for  the  crop,  aids  in  the  libera- 
tion of  mineral  plant  food,  and  prevents  the  soil  from  running  together  badly. 
This  constituent  must  be  supplied  to  the  soil  in  every  practical  way,  so  that  the 
amount  may  be  maintained  or  even  increased.  It  is  being  broken  down  during 
a large  part  of  the  year,  and  the  nitrates  produced  are  used  for  plant  growth. 

’Reported  by  Doctor  Bartow  and  associates,  of  the  Illinois  State  Water  Survey. 


1915] 


Lake  County 


51 


This  breaking  down  is  necessary,  but  it  is  also  quite  necessary  that  the  supply 
be  maintained. 

The  physical  effect  of  organic  matter  in  the  soil  is  to  produce  a granulation, 
or  mellowness,  very  favorable  for  tillage  and  the  development  of  plant  roots.  If 
continuous  cropping  takes  place,  accompanied  with  the  removal  of  the  corn  stalks 
and  straw,  the  amount  of  organic  matter  is  gradually  diminished  and  a condi- 
tion of  poor  tilth  will  ultimately  follow.  In  many  cases  this  already  limits  the 
crop  yields.  The  remedy  is  to  increase  the  organic-matter  content  by  plowing 
under  crop  residues,  such  as  corn  stalks,  straw,  and  clover.  Selling  these  prod- 
ucts from  the  farm,  burning  them,  or  feeding  them  and  not  returning  the  ma- 
nure, or  allowing  a very  large  part  of  the  manure  to  be  lost  before  it  is  returned 
to  the  land,  all  represent  bad  practice. 

One  of  the  chief  sources  of  loss  of  organic  matter  in  the  corn  belt  is  the 
practice  of  burning  the  corn  stalks.  Could  the  farmers  be  made  to  realize  how 
great  a loss  this  entails,  they  would  certainly  discontinue  the  practice.  Probably 
no  form  of  organic  matter  acts  more  beneficially  in  producing  good  tilth  than 
corn  stalks. ' It  is  true  that  they  decay  rather  slowly,  but  it  is  also  true  that  their 
durability  in  the  soil  after  partial  decomposition  is  exactly  what  is  needed  in 
the  maintenance  of  an  adequate  supply  of  humus. 

The  nitrogen  in  a ton  of  cornstalks  is  l1/^  times  that  in  a ton  of  manure,  and 
a ton  of  dry  corn  stalks  incorporated  with  the  soil  will  ultimately  furnish  as 
much  humus  as  4 tons  of  average  farm  manure;  but  when  burned,  both  the 
humus-making  material  and  the  nitrogen  which  these  stalks  contain  are  de- 
stroyed and  lost  to  the  soil. 

The  objection  is  often  raised  that  when  stalks  are  plowed  under  they  inter- 
fere very  seriously  in  the  cultivation  of  corn,  and  thus  indirectly  destroy  a great 
deal  of  corn.  If  corn  stalks  are  well  cut  up  and  then  turned  under  to  a depth 
of  51/2  to  6 inches  when  the  ground  is  plowed  in  the  spring,  very  little  trouble 
will  result. 

Where  corn  follows  corn,  the  stalks,  if  not  needed  for  feeding  purposes, 
should  be  thoroly  cut  up  with  a sharp  disk  or  stalk  cutter  and  turned  under. 
Likewise,  the  straw  should  be  returned  to  the  land  in  some  practical  way,  either 
directly  or  as  manure.  Clover  should  be  one  of  the  crops  grown  in  the  rotation, 
and  it  should  be  plowed  under  directly  or  as  manure  instead  of  being  sold  as  hay, 
except  when  manure  can  be  brought  back. 

It  must  be  remembered,  however,  that  in  the  feeding  of  hay,  or  straw,  or 
corn  stalks,  a great  destruction  of  organic  matter  takes  place,  so  that  even  if  the 
fresh  manure  were  returned  to  the  soil,  there  would  still  be  a loss  of  50  to  70 
percent  owing  to  the  destruction  of  organic  matter  by  the  animal.  If  manure  is 
allowed  to  lie  in  the  farmyard  for  a few  weeks  or  months,  there  is  an  additional 
loss  which  amounts  to  from  one-third  to  two-thirds  of  the  manure  recovered 
from  the  animal.  This  is  well  shown  by  the  results  of  an  experiment  conducted 
by  the  Maryland  Experiment  Station,  where  80  tons  of  manure  were  allowed  to 
lie  for  a year  in  the  farmyard  and  at  the  end  of  that  time  but  27  tons  remained, 
entailing  a loss  of  about  66  percent  of  the  manure.  Most  of  this  loss  occurs 
within  the  first  three  or  four  months,  when  fermentation,  or  ‘ ‘ heating,  ’ ’ is  most 
active.  Two  tons  of  manure  were  exposed  from  April  29  to  August  29,  by  the 


52 


Soil  Report  No.  9 


L Apnl, 


Canadian  Experiment  Station  at  Ottawa.  During  these  four  months  the  organic 
matter  was  reduced  from  1,938  pounds  to  655  pounds.  To  obtain  the  greatest 
value  from  the  manure,  it  should  be  applied  to  the  soil  as  soon  as  possible  after 
it  is  produced. 

It  is  a common  practice  in  the  corn  belt  to  pasture  the  corn  stalks  during 
the  winter  and  often  rather  late  in  the  spring  after  the  frost  is  out  of  the 
ground.  This  tramping  of  stock  sometimes  puts  the  soil  in  bad  condition  for 
working.  It  becomes  partially  puddled  and  will  be  cloddy  as  a result.  If 
tramped  too  late  in  the  spring,  the  natural  agencies  of  freezing  and  thawing, 
and  wetting  and  drying,  with  the  aid  of  ordinary  tillage,  fail  to  produce  good 
tilth  before  the  crop  is  to  be  planted.  Whether  the  crop  is  corn  or  oats,  it  neces- 
sarily suffers,  and  if  the  season  is  dry,  much  damage  may  result.  If  the  field  is 
put  in  corn,  a poor  stand  is  likely  to  follow,  and  if  put  in  oats,  a compact  soil  is 
formed  which  is  unfavorable  for  their  growth.  Sometimes  the  soil  is  worked 
when’too  wet.  This  also  produces  a partial  puddling  which  is  unfavorable  to 
physical,  chemical,  and  biological  processes.  The  bad  effect  will  be  greater  if 
cropping  has  reduced  the  organic  matter  below  the  amount  necessary  to  maintain 
good  tilth. 


UNIVERSITY  OF  ILLINOIS 


Agricultural  Experiment  Station 


SOIL  REPORT  NO.  10 


McLEAN  COUNTY  SOILS 


By  CYRIL  G.  HOPKINS,  J.  G.  HOSIER, 
E.  VAN  ALSTINE,  and  F.  W.  GARRETT 


URBANA,  ILLINOIS,  MAY,  1915 


State  Advisory  Committee  on  Soil  Investigations 

Ralph  Allen,  Delavan  A.  N.  Abbott,  Morrison 

P.  I.  Mann,  Gilman  J.  P.  Mason,  Elgin 

C.  V.  Gregory,  538  S.  Clark  Street,  Chicago 

Agricultural  ^Experiment  Station  Staff  on  Soil  Investigations 
Eugene  Davenport,  Director 


Cyril  G.  Hopkins,  Chief 

Soil  Survey — 

J.  G.  Mosier,  Chief 
A.  F.  Gustafson,  Associate 
S.  V.  Holt,  Associate 
H.  W.  Stewart,  Associate 
H.  C.  Wheeler,  Associate 

F.  A.  Fisher,  Assistant 

F.  M.  W.  Wascher,  Assistant 
R.  W.  Dickenson,  Assistant 

G.  E.  Gentle,  Assistant 
0.  I.  Ellis,  Assistant 

H.  A.  deWerff,  Assistant 
E.  F.  Torgerson,  Assistant 

Soil  Analysis— 

E.  Yan  Alstine,  Associate 
J.  P.  Aumer,  Associate 
W.  H.  Sachs,  Associate 
Gertrude  Niederman,  Assistant 
W.  R.  Leighty,  Assistant 
C.  B.  Clevenger,  Assistant 


Agronomy  and  Chemistry 
Soil  Experiment  Fields — 

J.  E.  Whitchurch,  Associate 

E.  E.  Hoskins,  Associate 

F.  C.  Bauer,  Associate 
F.  W,  Garrett,  Assistant 
H.  C.  Gilkerson,  Assistant 

H.  F.  T.  Fahrnkopf,  Assistant 
H.  J.  Snider,  Assistant 


Soil  Biology — 

A.  L.  Whiting,  Associate 
W.  R.  Schoonover,  Assistant 


Soils  Extension — 

C.  C,  Logan,  Associate 


INTRODUCTORY  NOTE 

About  two-thirds  of  Illinois  lies  in  the  corn  belt,  where  most  of  the  prairie 
lands  are  black  or  dark  brown  in  color.  In  the  southern  third  of  the  state,  the 
prairie  soils  are  largely  of  a gray  color.  This  region  is  better  known  as  the 
wheat  belt,  altho  wheat  is  often  grown  in  the  corn  belt  and  com  is  also  a com- 
mon crop  in  the  wheat  belt. 

Moultrie  county,  representing  the  com  belt;  Clay  county,  which  is  fairly 
representative  of  the  wheat  belt;  and  Hardin  county,  which  is  taken  to  repre- 
sent the  unglaciated  area  of  the  extreme  southern  part  of  the  state,  were  se- 
lected for  the  first  Illinois  Soil  Reports  by  counties.  While  these  three  county 
soil  reports  were  sent  to  the  Station’s  entire  mailing  list  within  the  state,  sub- 
sequent reports  are  sent  only  to  those  on  the  mailing  list  who  are  residents  of  the 
county  concerned,  and  to  any  one  else  upon  request. 

Each  county  report  is  intended  to  be  as  nearly  complete  in  itself  as  it 
is  practicable  to  make  it,  and,  even  at  the  expense  of  some  repetition,  each 
will  contain  a general  discussion  of  important  fundamental  principles  in  order 
to  help  the  farmer  and  landowner  understand  the  meaning  of  the  soil  fer- 
tility invoice  for  the  lands  in  which  he  is  interested.  In  Soil  Report  No.  1, 
“Clay  County  Soils,”  this  discussion  serves  in  part  as  an  introduction,  while 
in  this  and  other  reports,  it  will  be  found  in  the  Appendix ; but  if  necessary  it 
should  be  read  and  studied  in  advance  of  the  report  proper. 


McLEAN  COUNTY  SOILS 

By  CYRIL  G.  HOPKINS,  J.  G.  MOSIER,  E.  VAN  ALSTINE,  and  F.  W.  GARRETT 


McLean  county  is  located  in  the  central  part  of  Illinois  in  the  early  Wiscon- 
sin glaciation.  The  general  topography  is  undulating  to  slightly  rolling,  tho  an 
area  in  the  northwestern  part  of  tho  county  along  the  Mackinaw  river  is  in  part 
badly  broken. 

The  difference  in  topography  is  due  to  two  causes— glacial  action  and  stream 
erosion.  This  county  was  covered  by  two  ice  sheets  during  the  Glacial  period. 
At  that  time  snow  and  ice  accumulated  in  the  region  of  Labrador  and  to  the  west 
of  Hudson  Bay  to  such  an  amount  that  it  pushed  southward  until  a point  was 
reached  where  the  ice  melted  as  rapidly  as  it  advanced.  In  moving  across  the 
country,  the  ice  gathered  up  all  sorts  and  sizes  of  material,  including  clay,  silt, 
sand,  gravel,  boulders,  and  even  large  masses  of  rock.  Many  of  these  were  car- 
ried for  hundreds  of  miles  and  rubbed  against  the  surface  rocks  or  against  each 
other  until  ground  into  powder.  When  the  limit  of  advance  was  reached  by  the 
melting  of  the  ice,  this  material  accumulated  in  a broad  undulating  ridge,  or  mo- 
raine. When  the  ice  melted  away  more  rapidly  than  the  glacier  advanced,  the 
terminus  of  the  glacier  would  recede  and  leave  this  material  deposited  somewhat 
uniformly  over  the  tract,  marking  the  area  previously  covered  by  the  ice  sheet. 
Other  advances  occurred  which  built  up  other  moraines.  The  intervening  intermo- 
rainal  tracts  are  occupied  chiefly  by  level,  undulating,  "or  slightly  rolling  plains. 

The  material  transported  by  the  glacier  varied  with  the  character  of  the 
rocks  over  which  it  passed.  Granites,  limestones,  sandstones,  shales,  et  cetera, 
were  mixed  and  ground  up  together.  This  mixture  of  all  kinds  of  material — 
boulders,  clay,  silt,  sand,  and  gravel — is  called  boulder  clay,  till,  glacial  drift,  or 
simply  drift.  The  grinding  and  denuding  power  of  glaciers  is  enormous.  A 
mass  of  ice  100  feet  thick  exerts  a pressure  of  40  pounds  per  square  inch,  and  this 
ice  sheet  may  have  been  thousands  of  feet  in  thickness.  The  materials  carried 
along  in  this  mass  of  ice,  especially  the  boulders  and  pebbles,  became  powerful 
agents  for  grinding  and  wearing  away  the  surface  over  which  the  ice  passed. 
Preglacial  ridges  and  hills  were  rubbed  down,  valleys  were  filled  with  the  debris, 
and  the  surface  features  were  changed  entirely. 

McLean  county  was  first  covered  by  the  Illinois  glacier,  which  did  its  share 
toward  leveling  the  region  and  covering  it  with  a deposit  of  boulder  clay.  After 
this  a long  period  elapsed,  during  which  a soil  known  as  the  Sangamon  soil  was 
formed  from  this  glacial  deposit.  Then  another  advance  occurred,  known  as  the 
Iowan  glacier.  This  glacier  did  not  reach  McLean  county,  but  after  its  melt- 
ing the  state  was  covered  with  a deposit  of  wind-blown  loess,  which  buried  the 
old  soil  that  was  formed  from  the  Illinois  glacial  drift.  A new  soil  was  formed 
from  the  loess,  and  after  a long  period  had  elapsed  another  ice  advance  oc- 
curred— the  early  Wisconsin  glacier.  This  covered  the  entire  county,  bringing 


1 


2 


Soil  Report  No.  10 


[May, 


with  it  immense  quantities  of  the  material  which  now  covers  the  county  to  an 
average  depth  of  200  feet  and  in  many  places  reaches  a depth  of  250  feet.  The 
outer  limit  of  this  glaciation,  known  as  the  Shelbyville  moraine,  extends  to  the 
south-western  corner  of  McLean  county.  (See  the  state  soil  map  in  Bulletin  123.) 

The  early  Wisconsin  glacier  advanced  and  receded  in  this  county  at  least 
three  different  times,  building  up  terminal  moraines  with  each  advance.  The 
largest  of  these  is  the  Bloomington  moraine,  which  in  the  western  two-thirds  of 
the  county  is  made  up  of  a double  ridge,  coalescing  as  it  reaches  the  eastern  part. 
This  double  ridge  indicates  two  distinct  glacial  advances.  Another  moraine, 
kjnown  as  the  Cropsey  ridge,  occurs  in  the  northeastern  part  of  the  county.  A 
small  spur  from  the  Champaign  moraine  extends  into  the  southeastern  corner  of 
the  county,  and  it  is  likely  that  the  extension  of  this  was  covered  by  the  Bloom- 
ington moraine,  which  is  about  100  feet  higher  than  the  area  to  the  south.  The 
intermorainal  tracts  are  naturally  poorly  drained.  They  were  formerly  occupied 
by  swamps,  which  have  required  much  artificial  drainage. 

Physiography 

The  altitude  of  McLean  county  varies  from  600  to  about  900  feet  above  sea 
level,  with  an  average  of  approximately  750  feet.  The  highest  point,  920  feet, 
is  on  the  Bloomington  moraine  near  the  center  of  Township  23  North,  Range  4 
East.  The  altitude  of  some  of  the  points  are  as  follows:  Arrowsmith,  877  feet; 
Bellflower,  784 ; Bloomington,  821 ; Chenoa,  723  ; Colfax,  742  ; Cropsey,  802  ; Dan- 
vers, 808  ; Downs,  794  ; Ellsworth,  863  ; Funk’s  Grove,  694  ; Gillum,  820  ; Gridley, 
752;  Hudson,  768;  Lexington,  746;  Leroy,  780;  McLean,  708;  Normal,  790;  Say- 
brook,  786 ; Weedman,  725. 

The  county  is  divided  into  four  drainage  areas : the  Mackinaw  in  the  north 
and  northwest,  the  Sangamon  in  the  east,  Rooks  creek,  a branch  of  the  Vermilion, 
in  the  northeast,  and  Sugar  creek  and  its  branches  in  the  south  and  southwest. 
All  these  streams,  however,  flow  into  the  Illinois  river.  Drainage  is  naturally 
well  developed  in  the  western  half  of  the  county. 

Soil  Material  and  Soil  Types 

The  early  Wisconsin  glacier  left  extensive  deposits  of  boulder  clay  over  the 
county,  but  the  soils  as  a general  rule  are  not  formed  from  this  material.  After 
the  Wisconsin  glacier,  the  county  was  again  covered  by  a deposit  of  fine  wind- 
blown material,  loessial  in  character,  varying  from  2 to  7 feet  in  depth,  and  it  is 
from  this  loess  that  the  soil  has  generally  been  formed.  In  very  small  areas  on 
some  of  the  more  rolling  parts,  this  fine  material  has  been  removed  to  such  an 
extent  that  the  exposed  boulder  clay  may  constitute  the  soil  material. 

The  soils  of  the  county  are  divided  into  four  classes,  as  follows : 

(a)  Upland  prairie  soils,  rich  in  organic  matter.  These  were  originally 
covered  with  wild  prairie  grasses,  the  partially  decayed  roots  of  which  have  been 
the  source  of  the  organic  matter.  The  flat  prairie  land  contains  the  higher 
amount  of  this  constituent  because  the  grasses  and  roots  grew  more  luxuriantly 
there,  and  the  higher  moisture  content  preserved  them  from  complete  decay. 

(b)  Upland  timber  soils,  including  those  zones  along  stream  courses  over 
which  for  a long  period  of  time  forests  once  extended.  These  soils  contain  much 


1915 ] 


McLean  County 


3 


Table  1. — Soil  Types  op  McLean  County 


Soil 

type  Name  of  type 

No.  | 

Area 
in  square 
miles 

Area  | 
in  acres 

Percent 
of  total 
area 

926  ) 
1126  \ 
1120 
1120.2 
1128 
990  ) 
1190  f 

(a)  Upland  Prairie  Soils  (page  24) 

847.38 

168.69 

4.04 

2.42 

.15 

542  323.2 
107  961.6 
2 585.6 
1 548.8 
96.0 

72.602 

14.474 

.345 

.207 

.012 

Gravelly  black  clay  loam 

Brown-gray  silt  loam  on  tight  clay 

934  ) 

1134  f 
935) 

1135  5 

(b)  Upland  Timber  Soils  (page  29) 

Yellow-gray  silt  loam  

Yellow  silt  loam  - 

73.42 

27.43 

46  988.8 
17  555.2 

6.227 

2.357 

1527 

1526.2 

1534.2 

(c)  Terrace  Soils  (page  37) 

Brown  silt  loam  over  gravel  

Brown  silt  loam  on  gravel  

Yellow-gray  silt  loam  on  gravel  

.26 

1.77 

.97 

166.4 
1 132.8 
620.8 

.002 

.152 

.083 

1401 

1426 

1454 

(d)  Swamp  and  Bottom-Land  Soils  (page  38) 
Deep  peat  

.13 

23.88 

18.06 

83.2 
15  283.2 
11  558.4 

.011 

2.008 

1.520 

Deep  brown  silt  loam 

\ I i v < '( 1 loam  

Total  

i ifiRfin 

747  904  0 

100.000 

less  organic  matter,  because  the  large  roots  of  dead  trees  and  the  surface  accu- 
mulations of  leaves,  twigs,  and  fallen  trees  were  burned  by  forest  fires  or  suffered 
almost  complete  decay.  The  timber  lands  are  divided  chiefly  into  two  classes — 
the  undulating  and  the  hilly  areas. 

(c)  Terrace  soils.  These  have  been  formed  by  deposits  from  flooded 
streams  overloaded  with  coarse  sediment  at  the  time  of  the  melting  of  the  glacier. 
Finer  deposits  which  were  later  made  upon  the  coarse  gravelly  material  now  con- 
stitute the  soil. 

(d)  Swamp  and  bottom  lands,  which  include  the  flood  plains  along  streams 
and  some  small  peaty  swamp  areas. 

Table  1 gives  the  area  of  each  type  of  soil  in  the  county  and  its  percentage 
of  the  total  area.  It  will  be  observed  that  721/2  percent  of  the  area  consists  of 
brown  silt  loam,  141/2  percent  of  black  clay  loam,  and  6 percent  of  yellow-gray 
silt  loam,  these  three  types  covering  93  percent  of  the  county.  The  accompany- 
ing maps  show  the  location  and  boundary  lines  of  every  type  of  soil  in  the  county, 
even  down  to  areas  of  a few  acres. 

THE  INVOICE  AND  INCREASE  OF  FERTILITY  IN  McLEAN 
COUNTY  SOILS 
Soil  Analysis 

In  order  to  avoid  confusion  in  applying  in  a practical  way  the  technical 
information  contained  in  this  report,  the  results  are  given  in  the  most  simplified 
form.  The  composition  reported  for  a given  soil  type  is,  as  a rule,  the  average 
of  many  analyses,  which,  like  most  things  in  nature,  show  more  or  less  variation ; 
but  for  all  practical  purposes  the  average  is  most  trustworthy  and  sufficient. 


Soil  Eepoet  No.  10 


[May, 


(See  Bulletin  123,  which  reports  the  general  soil  survey  of  the  state,  together 
with  many  hundred  individual  analyses  of  soil  samples  representing  twenty-five 
of  the  most  important  and  most  extensive  soil  types  in  the  state.) 

The  chemical  analysis  of  a soil  gives  the  invoice  of  fertility  actually  pres- 
ent in  the  soil  strata  sampled  and  analyzed,  but,  as  explained  in  the  Appendix, 
the  rate  of  liberation  is  governed  by  many  factors.  Also,  as  there  stated,  prob- 
ably no  agricultural  fact  is  more  generally  known  by  farmers  and  landowners 
than  that  soils  differ  in  productive  power.  Even  tho  plowed  alike  and  at  the 
same  time,  prepared  the  same  way,  planted  the  same  day  with  the  same  kind 
of  seed,  and  cultivated  alike,  watered  by  the  same  rains  and  warmed  by  the 
same  sun,  nevertheless  the  best  acre  may  produce  twice  as  large  a crop  as  the 
poorest  acre  on  the  same  farm,  if  not,  indeed,  in  the  same  field;  and  the  fact 
should  be  repeated  and  emphasized  that  the  productive  power  of  normal  soil 
in  humid  sections  depends  upon  the  stock  of  plant  food  contained  in  the  soil 
and  upon  the  rate  at  which  it  is  liberated. 

The  fact  may  be  repeated,  too,  that  crops  are  not  made  out  of  nothing. 
They  are  composed  of  ten  different  elements  of  plant  food,  every  one  of  which 
is  absolutely  essential  for  the  growth  and  formation  of  every  agricultural  plant. 
Of  these  ten  elements  of  plant  food,  only  two  (carbon  and  oxygen)  are  secured 
from  the  air  by  all  plants,  only  one  (hydrogen)  from  water,  while  seven  are 
secured  from  the  soil.  Nitrogen,  one  of  these  seven  elements  secured  from  the 
soil  by  all  plants,  may  also  be  secured  from  the  air  by  one  class  of  plants 
(legumes)  in  case  the  amount  liberated  from  the  soil  is  insufficient.  But  even 
the  leguminous  plants  (which  include  the  clovers,  peas,  beans,  alfalfa,  and 
vetches),  in  common  with  other  agricultural  plants,  secure  from  the  soil  alone 
six  elements  (phosphorus,  potassium,  magnesium,  calcium,  iron,  and  sulfur)  and 
also  utilize  the  soil  nitrogen  so  far  as  it  becomes  soluble  and  available  during 
their  period  of  growth. 

Table  A in  the  Appendix  shows  the  requirements  of  large  crops  for  the  five 
most  important  plant-food  elements  which  the  soil  must  furnish.  (Iron  and 
sulfur  are  supplied  normally  from  natural  sources  in  sufficient  abundance,  com- 
pared with  the  amounts  needed  by  plants,  so  that  they  are  never  known  to  limit 
the  yield  of  common  farm  crops.) 

In  Table  2 are  reported  the  amounts  of  organic  carbon  ( the  best  measure  of 
the  organic  matter)  and  the  total  amounts  of  the  five  important  elements  of  plant 
food  contained  in  2 million  pounds  of  the  surface  soil  of  each  type, — the  plowed 
soil  of  an  acre  about  6%  inches  deep.  In  addition,  the  table  shows  the  amount 
of  limestone  present,  if  any;  or  the  soil  acidity  as  measured  by  the  amount  of 
limestone  required  to  neutralize  the  acidity  existing  in  the  soil. 

The  soil  to  the  depth  indicated  includes  at  least  as  much  as  is  ordinarily 
turned  with  the  plow,  and  represents  that  part  with  which  the  farm  manure, 
limestone,  phosphate,  or  other  fertilizer  applied  in  soil  improvement  is  incor- 
porated. It  is  the  soil  stratum  that  must  be  depended  upon  in  large  part  to 
furnish  the  necessary  plant  food  for  the  production  of  crops,  as  will  be  seen  from 
the  information  given  in  the  Appendix.  Even  a rich  subsoil  has  little  or  no 
value  if  it  lies  beneath  a worn-out  surface,  for  the  weak,  shallow-rooted  plants 
will  be  unable  to  reach  the  supply  of  plant  food  in  the  subsoil.  If,  however, 
the  fertility  of  the  surface  soil  is  maintained  at  a high  point,  then  the  plants, 


SOIL  SURVEY  MAP  OF  McLEAN  COUNTY 

UNIVERSITY  OF  ILLINOIS  AGRICULTURAL  EXPERIMENT  STATION 


LEGEND 


(a)  UPLAND  PRAIRIE  SOILS 


(b)  UPLAND  TIMBER  SOILS 


(d)  SWAMP  AND  BOTTOM-LAND  SOILS 


Brown  silt  loam  on  gravel 


Black  clay  loam 


Gravelly  black  clay  loam 


Yellow-gray  silt  loam 


(c)  TERRACE  SOILS 

Brown  silt  loam  over  gravel 


1428  Deep  brown  silt  loam 


Mixed  loam 
j Deep  peat 

Early  Wisconsin  Morain 


NORTH  W EST  SH  EET 


.1 VINGSTON 


WOOD  FOB-13 


IPEOfll 


Cuds  on 


fLI  NOt 


1 ; 
)l  \ 

PJ 

p 

1 1 6 CO 
O 

J u 

A HOEN& CO. BALTIMORE. 


1V15] 


McLean  County 


5 


with  a vigorous  start  from  the  rich  surface  soil,  can  draw  upon  the  subsurface 
and  subsoil  for  a greater  supply  of  plant  food. 

By  easy  computation  it  will  be  found  that  the  most  common  prairie  soil  of 
McLean  county  does  not  contain  more  than  enough  total  nitrogen  in  the  plowed 
soil  for  the  production  of  maximum  crops  for  forty  years,  while  the  upland 
timber  soils  contain,  as  an  average,  much  less  nitrogen  than  the  prairie  land. 

With  respect  to  phosphorus,  the  condition  differs  only  in  degree,  more  than 
eight-tenths  of  the  soil  area  of  the  county  containing  no  more  of  that  element 
than  would  be  required  for  fifteen  crop  rotations  if  such  yields  were  secured  as 
are  suggested  in  Table  A of  the  Appendix.  It  will  be  seen  from  the  same  table 
that  with  the  cereals  about  three-fourths  of  the  phosphorus  taken  from  the  soil  is 
deposited  in  the  grain,  while  only  one-fourth  remains  in  the  straw  or  stalks. 

On  the  other  hand,  the  potassium  is  sufficient  for  28  centuries  if  only  the 
grain  is  sold,  or  for  450  years  even  if  the  total  crops  should  be  removed  and 
nothing  returned.  The  corresponding  figures  are  about  2,000  and  500  years  for 
magnesium,  and  about  9,000  and  200  years  for  calcium.  Thus,  when  measured 
by  the  actual  crop  requirements  for  plant  food,  potassium  is  no  more  limited 
than  magnesium  and  calcium ; and  as  explained  in  the  Appendix,  with  magne- 
sium, and  more  especially  with  calcium,  we  must  also  consider  the  fact  that  loss 
by  leaching  is  far  greater  than  by  cropping. 

These  general  statements  relating  to  the  total  quantities  of  plant  food  in 
the  plowed  soil  certainly  emphasize  the  fact  that  the  supplies  of  some  of  these 
necessary  elements  of  fertility  are  extremely  limited  when  measured  by  the  needs 
of  large  crop  yields  for  even  one  or  two  generations  of  people,  and,  with  a popu- 
lation increasing  by  more  than  20  percent  each  decade,  the  future  needs  of  the 


Table  2. — Fertility  in  the  Soils  of  McLean  County,  Illinois 
Average  pounds  per  acre  in  2 million  pounds  of  surface  soil  (about  0 to  6%  inches) 


Soil 

Total 

Total 

Total 

Total 

Total 

Total 

Lime- 

Soil 

type 

Soil  type 

organic 

nitro- 

phos- 

potas- magne- 

cal- 

stone 

acid- 

No. 

carbon 

gen 

phorus 

sium  1 

sium 

cium 

present 

ity 

Upland  Prairie  Soils 


1126 

Brown  silt  loam I 

57  410  4 870 

1 120  1 

36  640 

8 350 

9 560 

60 

1120 

Black  clay  loam 

91  370  8 160 

2 000 

34  210 

16  580 

31  240  1 Often 

Rarely 

1120.2 

Gravelly  black  clay  loam . 

65  180 i 6 020 

1 620 

32  520 

23  920 

74  740  170  760 

1128 

Brown-gray  silt  loam  on 

tight  clay  1 

47  880 ! 4 200 

1 380 

36  220 

6 780 

7 300 

120 

1190 

Gravelly  loam  1 

I 32  520 | 3 040 

1 000  1 

35  240 

8 240 

6 780  1 

20 

Upland  Timber  Soils 

1134 

1 Yellow-gray  silt  loam.  . I 

33  670 1 2 940 

! 1 050  H 

[35  910 

| 6 220 

7 820 

1 60 

1135 

1 Yellow  silt  loam 

17  780 | 1 650 

| 750 

35  440 

7 330 

6 420  I 

l 150 

Terrace 

Soils 

1527 

Brown  silt  loam  over 

1 

gravel  

65  180!  5 980 

1 420 

36  180 

8 700 

7 140 

40 

1526.2 

Brown  silt  loam  on  gravel 

41  930  3 770 

1 080 

38  430 

8 050 

7 480 

40 

1534.4 

Yellow-gray  silt  loam  on 

gravel  

35  520  3 660 

1 080 

37  000 

6 700 

7 880  | 

20 

Swamp  and  Bottom-Land  Soils 


1401  Deep  peat 

318  850129  530  1 2 710  1 6 240:  5 610 

33  460 

3 930 

1426  [Deep  brown  silt  loam.  . . 

79  940  6 620  2 120  38  980  11  260 

16  500 

60 

1454  |Mixed  loam  

65  760)  5 980  1 1 760  | 42  620  14  080 

20  100 

8 120 

6 


Soil  Report  No.  10 


[May, 


people  dependent  upon  the  corn  belt  are  likely  to  be  far  greater  than  the  re- 
quirements of  the  past,  and  soil  fertility  and  crop  yields  should  not  decrease  but 
increase. 

In  the  production  of  general  farm  crops,  McLean  is  now  the  leading  county 
in  the  United  States.  The  only  rival  counties  for  the  position  of  greatest  in  agri- 
culture are  Los  Angeles,  Cal.,  and  Lancaster,  Pa.  The  crop  values  reported  for 
these  counties  by  the  latest  United  States  census  (for  1909)  are  as  follows: 


1 

County 

Value  of 
all 

crops 

Value  of  all 
crops  except 
tobacco,  vegetables, 
fruits,  and  nuts 

Los  Angeles,  California  

$14  720  884 
13  059  588 

$6  734  259 
8 617  170 
12  690  404 

Lancaster,  Pennsylvania  

McLean,  Illinois 

12  811  500 

McLean  county  produced  16  million  bushels  of  corn  in  1909,  while  8 million 
were  produced  in  the  six  New  England  states,  less  than  10  million  in  the  eleven 
Western  states,  18  million  in  Maryland,  21  million  in  South  Carolina,  39  mil- 
lion in  Georgia,  and  390  million  in  Illinois.  And  yet  McLean  county  produced 
but  little  more  than  half  a crop,  measured  by  its  normal  climatic  possibilities  un- 
der rational  systems  of  soil  improvement.  The  ten-year  average  yield  of  corn  for 
McLean  county  is  39  bushels  per  acre,  according  to  the  Statistical  Reports  of  the 
Illinois  State  Board  of  Agriculture  for  the  years  1905  to  1914.  During  the  same 
ten  years  the  average  acre-yield  was  78.3  bushels  on  the  University  of  Illinois 
North  Farm  at  Urbana,  where  organic  manures,  limestone,  and  phosphorus  had 
been  applied.  (See  records  of  Plots  6 and  7,  Tables  3 and  4,  pages  10  and  11.) 
Such  results  should  induce  careful  study  of  the  individual  farm  with  its  particu- 
lar soil  type  or  types,  in  order  that  the  best  methods  may  be  adopted  for  soil  im- 
provement and  preservation. 

The  variation  among  the  different  types  of  soil  in  McLean  county  with  re- 
spect to  their  content  of  important  plant-food  elements  is  very  marked.  Thus  the 
richest  prairie  land  (black  clay  loam)  contains  from  three  to  five  times  as  much 
nitrogen  and  twice  as  much  phosphorus  as  the  common  upland  timber  soils ; and 
the  deep  peat  soil  contains  eighteen  times  as  much  nitrogen  but  only  one-sixth  as 
much  potassium  as  the  yellow  silt  loam.  The  most  significant  facts  revealed  by 
the  investigation  of  the  McLean  county  soils  are  the  lack  of  limestone  and  the 
low  phosphorus  content  of  the  common  prairie  soil  and  of  the  most  extensive  tim- 
ber type,  which  combined  cover  nearly  80  percent  of  the  entire  county.  And  yet 
both  of  these  deficiencies  can  be  overcome  at  relatively  small  expense  by  the  ap- 
plication of  ground  limestone  and  fine-ground  raw  rock  phosphate;  and,  after 
these  are  provided,  clover  can  be  grown  with  more  certainty  and  in  greater  abun- 
dance, and  nitrogen  can  thus  be  secured  from  the  inexhaustible  supply  in  the  air. 
If  the  clover  is  then  returned  to  the  soil,  either  directly  or  in  farm  manure,  the 
combined  effect  of  limestone,  phosphorus,  and  nitrogenous  organic  matter,  with 
a good  rotation  of  crops,  will  in  time  double  the  yield  of  corn  and  other  crops 
on  most  farms. 

Fortunately,  some  definite  field  experiments  have  already  been  conducted  on 
brown  silt  loam,  the  most  extensive  type  of  soil  in  the  early  Wisconsin  glaciation, 
as  at  Urbana  in  Champaign  county,  at  Sibley  in  Ford  county,  and  at  Bloomington 


N O RTH EAST  SHE ET 


LEGEND 


UPLAND  PRAIRIE  SOILS 
j Brown  silt  loam 

I Brown  silt  loam  on  gravel 
| Black  clay  loam 
| Gravelly  black  clay  loam 
| Brown-gray  silt  loam  on  tight  clay 
j Gravelly  loam. 

UPLAND  TIMBER  SOILS 
Yellow-grav  silt  loam 

Yellow  silt  loam 


(c)  TERRACE  SOILS 

Brown  silt  loam  over  gravel 


Yellow-gray  silt  loam  on  gravel 


(d)  SWAMP  AND  BOTTOM-LAND  SOILS 
Deep  brown  silt  loam 


Deep  peat 
900  Early  Wisconsin  Moraines 

1100  Early  Wisconsin  I ntermorainal  Areas 


f.  COUNTY 

STATTOV 


1915] 


McLean  County 


in  McLean  county.  Before  considering  in  detail  the  individual  soil  types,  it 
seems  advisable  to  study  some  of  the  results  already  obtained  where  definite 
systems  of  soil  improvement  have  been  tried  out  on  some  of  these  experiment 
fields  in  different  parts  of  central  Illinois. 

Results  of  Field  Experiments  at  Urbana 

A three-year  rotation  of  corn,  oats,  and  clover  was  begun  on  the  North  Farm 
at  the  University  of  Illinois  in  1902,  on  three  fields  of  typical  brown  silt  loam 
prairie  land  which,  after  twenty  years  or  more  of  pasturing,  had  grown  corn  in 
1895,  1896,  and  1897  (when  careful  records  were  kept  of  the  yields  produced), 
and  had  then  been  cropped  with  clover  and  grass  on  one  field  (Series  100),  oats 
on  another  (Series  200),  and  oats,  cowpeas,  and  corn  on  the  third  field  (Series 
300)  until  1901. 

From  1902  to  1910  the  three-year  rotation  (with  cowpeas  in  place  of  clover 
in  1902)  was  followed;  the  average  yields  are  recorded  in  Table  3.  A small  crop 
of  cowpeas  in  1902  and  a partial  crop  of  clover  in  1904  constituted  all  the  hay 
harvested  during  the  first  rotation,  mammoth  clover  grown  in  1903  having  lodged 
so  that  it  was  plowed  under.  (The  yields  were  taken  by  carefully  weighing  the 
clover  from  small  representative  areas,  but  while  the  differences  were  thus  ascer- 
tained and  properly  credited  temporarily  to  the  different  soil  treatments,  they 
must  ultimately  reappear  in  subsequent  crop  yields,  and  consequently  the  1903 
clover  crop  is  omitted  from  Table  3 in  computing  yields  and  values.)  The  aver- 
age yields  given  represent  one-third  of  the  two  small  crops. 

From  1902  to  1907  legume  cover  crops  (Le),  such  as  cowpeas  and  clover, 
were  seeded  in  the  corn  at  the  last  cultivation  on  Plots  2,  4,  6,  and  8,  but  the 
growth  was  small  and  the  effect,  if  any,  was  to  decrease  the  returns  from  the 
regular  crops.  Since  1907  crop  residues  (R)  have  been  returned  to  those  plots. 
These  consist  of  the  stalks  of  corn,  the  straw  of  small  grains,  and  all  legumes 
except  alfalfa  hay  and  the  seed  of  clover  and  soybeans. 

On  Plots  3,  5,  7,  and  9,  manure  (M)  was  applied  for  corn  at  the  rate  of 
6 tons  per  acre  during  the  second  rotation,  and  subsequently  as  many  tons  of 
manure  have  been  applied  as  there  were  tons  of  air-dry  produce  harvested  from 
the  corresponding  plots. 

Lime  (L)  was  applied  on  Plots  4 to  10  at  the  rate  per  acre  of  250  pounds 
of  air-slaked  lime  in  1902  and  600  pounds  of  limestone  in  1903.  Subsequently 
2 tons  per  acre  of  limestone  was  applied  to  these  plots  on  Series  100  in  1911,  on 
Series  200  in  1912,  on  Series  300  in  1913,  and  on  Series  400  in  1914;  also  2y2 
tons  per  acre  on  Series  500  in  1911,  two  more  fields  having  been  brought  into 
rotation,  as  explained  on  page  8. 

Phosphorus  (P)  has  been  applied  on  Plots  6 to  9 at  the  rate  of  25  pounds  per 
acre  per  annum  in  200  pounds  of  steamed  bone  meal ; but  beginning  with  1908, 
one  half  of  each  phosphorus  plot  has  received  600  pounds  of  rock  phosphate  in 
place  of  the  200  pounds  of  bone  meal,  the  usual  practice  being  to  apply  and  plow 
under  at  one  time  all  phosphorus  and  potassium  required  for  the  rotation. 

Potassium  (K=kalium)  has  been  applied  on  Plots  8 and  9 at  the  yearly 
rate  of  42  pounds  per  acre  in  100  pounds  of  potassium  sulfate,  regularly  in  con- 
nection with  the  bone  meal  and  rock  phosphate. 

On  Plot  10  about  five  times  as  much  manure  and  phosphorus  are  applied 
as  on  the  other  plots,  but  this  “extra  heavy”  treatment  was  not  begun  until 


8 


Soil  Report  No.  10 


[May, 


1906,  only  the  usual  lime,  phosphorus,  and  potassium  having  been  applied  in 
previous  years.  The  purpose  in  making  these  heavy  applications  is  to  try  to 
determine  the  climatic  possibilities  in  crop  yields  by  removing  the  limitations 
of  inadequate  fertility. 

Series  400  and  500  were  cropped  in  corn  and  oats  from  1902  to  1910,  but 
the  corresponding  plots  were  treated  the  same  as  in  the  three-year  rotation. 
Beginning  with  1911,  the  five  series  have  been  used  for  a combination  rotation, 
wheat,  corn,  oats,  and  clover  being  rotated  for  five  years  on  four  fields,  while 
alfalfa  occupies  the  fifth  field,  which  is  then  to  be  brought  under  the  four-crop 
system  to  make  place  for  alfalfa  on  one  of  the  other  fields  for  another  five-year 
period,  and  so  on.  (See  Table  4.) 

From  1911  to  1914  soybeans  were  substituted  three  years  because  of  clover 
failure;  accordingly  three-fourths  of  the  soybeans  and  one-fourth  of  the  clover’ 
are  used  to  compute  values.  Alfalfa  from  the  1911  seeding  so  nearly  failed  that 
after  cutting  one  crop  in  1912  the  field  was  plowed  and  reseeded.  The  average 
yield  reported  for  alfalfa  in  Table  4 is  one-fourth  of  the  combined  crops  of  1912, 
1913,  and  1914. 

The  “higher  prices”  allowed  for  produce  are  $1  a bushel  for  wheat  and 
soybeans,  50  cents  for  corn,  40  cents  for  oats,  $10  for  clover  seed,  and  $10  a ton 
for  hay;  while  the  “lower  prices”  are  70  percent  of  these  values,  or  70  cents 


Plate  1. — Clover  in  1913  on  Urbana  Field 
Farm  Manure  Applied 
Yield,  1.43  Tons  per  Acre 


(a)  UPLAND  PRAIRIE  SOILS 

20.2  Gravelly  black  clay  loam 


Brown  silt  loam  on  gravel 


Brown-gray  silt  loam  on  tight  clay 
Gravelly  loam 


(b)  UPLAND  TIMBER  SOILS 
Yellow-gray  silt  loam 

Yellow  silt  loam 


SOIL  SURVEY  MA 

UNIVERSITY  OF  ILLINOIS  AGli 


SOUTHWEST  SHEET 


VP7//A 


rtTT 


COUNTY 


(d)  SWAMP  AND  BOTTOM-LAND  SOILS 


(c)  TERRACE  SOILS 


1113 

— ss — 

^rr 

92VW 
—Sift?  r 

y 1' 

Brown  silt  loam  over  gravel 
Brown  silt  loam  on  gravel 


Yellow-gray  silt  loam 


Deep  brown  silt  loam 


Mixed  loam 


Deep  peat 


900  Early  Wisconsin  Moraines 

coo  Early  Wisconsin  I nter'morainal  Areas 

Scale 

o M*  Vz  i Mile  s 


OF  McLEAN  COUNTY 

CULTURAL  EXPERIMENT  STATION 


1915 ] 


McLean  County 


9 


for  wheat  and  soybeans,  35  cents  for  corn,  28  cents  for  oats,  $7  for  clover  seed, 
and  $7  a ton  for  hay.  The  double  set  of  values  is  used  to  emphasize  the  fact 
that  a given  practice  may  or  may  not  be  profitable,  depending  upon  the  prices 
of  farm  produce.  The  lower  prices  are  conservative,  and  unless  otherwise  stated, 
they  are  the  values  regularly  used  in  the  discussion  of  results.  It  should  be 
understood  that  the  increase  produced  by  manures  and  fertilizers  requires  in- 
creased expense  for  binding  twine,  shocking,  stacking,  baling,  threshing,  haul- 
ing, storing,  and  marketing.  Measured  by  the  average  Illinois  prices  for  the 
past  ten  years,  these  lower  values  are  high  enough  for  farm  crops  standing  in 
the  field  ready  for  the  harvest. 

The  cost  of  limestone  delivered  at  the  farmers’  railroad  station  in  carload 
lots  averages  about  $1.25  per  ton.  Steamed  bone  meal  in  carloads  costs  from 
$25  to  $30  per  ton.  Fine-ground  raw  rock  phosphate  containing  from  260  to 
280  pounds  of  phosphorus,  or  as  much  as  the  bone  meal  contains,  ton  for  ton, 
but  in  less  readily  available  form,  usually  costs  the  farmer  from  $6.50  to  $7.50  per 
ton  in  carloads.  (Acid  phosphate  carrying  half  as  much  phosphorus,  but  in 
soluble  form,  commonly  costs  from  $15  to  $17  per  ton  delivered  in  carload  lots 
in  central  Illinois.)  Under  normal  conditions  potassium  costs  about  6 cents  a 
pound,  or  $2.50  per  acre  per  annum  for  the  amount  applied  in  these  experi- 
ments, the  same  as  the  cost  of  200  pounds  of  steamed  bone  meal  at  $25  per  ton. 


Plate  2. — Clover  in  1913  on  Urbana  Field 
Farm  Manure,  Limestone,  and  Phosphorus  Applied 
Yield,  2.90  Tons  per  Acre 


[May, 


SOUTHEAST  SHEET 


{ 

) 

i 


1915 ] 


McLean  County 


11 


Table  4. — Yields  per  Acre,  Four-year  Averages,  1911-19  Urbana  Field 
Brown  Silt  Loam  Prairie;  Early  Wisconsin  Gl  vtion 


Serial 

plot 

No. 

Soil 

treat- 

ment 

Wheat, 

bu. 

Corn, 

bu. 

Oats, 

bu. 

Soybeans-3, 
tons  (bu.) 

1 -iver-1, 
tons  'bu.) 

1“ 

07777777. 

18.3 

50.8 

39.8 

L6C* 

1.70 

2 

R 

19.7 

53.8 

40.6 

(2°.D  1 

( -74) 

3 

M 

20.3 

59.3 

48.8 

1.60  7 

1.43 

4 

EL 

22.3 

55.7 

42.8 

(19.0) 

(1.03) 

5 

ML 

24.9 

58.6 

51.6 

1.66 

1.94 

6~~ 

rlp.7  77 

37.4  “ 

62.2 

58.7 

(21.0)^7 

(2.48) 

7 

MLP .... 

36.6 

63.8 

60.9 

1.88yA 

2.90 

8 

RLPIC . . . 

36.1 

58.9 

59.1 

(22.2) 

(1.41) 

9 

MLPK. . 

35.3 

1 59.6 

65.1 

2.09  . 

2.72 

10 

MxLPx . . 

43.5 

| 55.7 

67.2 

2.14 

2.94 

To  these  cash  investments  must  he  added  the  expense  od 
ing  the  materials.  This  will  vary  with  the  distance  from 
road  station,  with  the  character  of  roads,  and  with  the  farnl 
diate  requirements  of  other  lines  of  farm  work.  It  is  the  pa} 
such  materials  in  advance  to  be  shipped  when  specified,  so 
ceived  and  applied  when  other  farm  work  is  not  too  press| 
when  the  roads  are  likely  to  be  in  good  condition. 

The  practice  of  seeding  legume  cover  crops  in  the  cornfie  d at  the  last  culti- 
vation where  oats  are  to  follow  the  next  year  has  not  been  found  profitable,  as  a 
rule,  on  good  corn-belt  soil;  but  the  returning  of  the  crop  residues  to  the  land 
may  maintain  the  nitrogen  and  organic  matter  equally  as  well  as  the  hauling  and 
spreading  of  farm  manure, — and  this  makes  possible  permanent  systems  of  farm- 
ing on  grain  farms  as  well  as  on  live-stock  farms,  provided,  of  course,  that  other 
essentials  are  supplied.  (Clover  with  oats  or  wheat,  as  a cove-crop  to  be  plowed 
under  for  corn,  often  gives  good  results.) 

At  the  lower  prices  for  produce,  manure  (6  tons  per  acre)  was  wbTfciT$L05 
a ton  as  an  average  for  the  first  three  years  it  was  applied  (1905  to  1907).  The' 
next  roiation  the  average  application  of  10.21  tons  per  acre  on  Plot  3 was  worth 
$10.09,  or  99  cents  a ton.  The  last  four  years,  1911  to  1914,  the  average  amount 
applied  (once  for  the  rotation)  on  Plot  3 was  11.35  tons  per  acre,  worth  $6.42, 
or  57  cents  a ton,  as  measured  by  its  effect  on  the  wheat,  corn,  oats,  soybeans, 
and  clover.  Thus,  as  an  average  of  the  ten  years’  results,  the  farm  manure  ap- 
plied to  Plot  3 has  been  worth  84  cents  a ton  on  common  corn-belt  prairie  soil, 
with  a good  crop  rotation  including  legumes.  During  the  last  rotation  period 
moisture  has  been  the  limiting  factor  to  such  an  extent  as  probably  to  lessen  the 
effect  of  the  manure. 

Aside  from  the  crop  residues  and  manure,  each  addition  affords  a duplicate 
test  as  to  its  effect.  Thus  the  effect  of  limestone  is  ascertained  by  comparing  Plots 
4 and  5,  not  with  Plot  1,  but  with  Plots  2 and  3 ; and  the  effect  of  phosphorus  is 
ascertained  by  comparing  Plots  6 and  7 with  Plots  4 and  5,  respectively. 

As  a general  average,  the  plots  receiving  limestone  have  produced  $1.22  an 
acre  a year  more  than  those  without  limestone,  and  this  corresponds  to  more  than 
$6  a ton  for  all  of  the  limestone  applied;  but  the  amounts  used  before  1911 
were  so  small  and  the  results  vary  so  greatly  with  the  different  plots,  crops,  and 
seasons  that  final  conclusions  cannot  be  drawn  until  further  data  are  secured, 


12 


Soil  Eeport  No.  10 


\May, 


nd  highest 


the  first  2-ton  application*  having  been  completed  only  for  1914.  However,  all 
comparisons  by  rotation  riods  show  some  increase  for  limestone,  varying  from 
82  cents  on  three  acre-  Plot  4)  during  the  first  rotation,  to  $8.75  on  five  acres 
(Plot  j)  as  an  avera',e  of  the  last  four  years;  and  the  need  of  limestone  for  best 
'rofits  seems  well  established. 

of  duplicate  trials  (Plots  6 and  7),  phosphorus  in  bone  meal 
alued  at  $1.92  per  acre  per  annum  for  the  first  three  years 
n 'xt  three;  and  the  corresponding  subsequent  average  in- 
1 and  raw  phosphate  (one-half  plot  of  each)  were  $5.12  for 
d $5.36  for  the  last  four  years,  1911  to  1914.  The  annual 
phosphorus  is  $2.80  in  bone  meal  at  $28  a ton,  or  $2.10  for 
ton. 

ed  at  an  estimated  cost  of  $2.50  an  acre  a year,  seemed  to 
ses,  as  an  average,  during  the  first  and  second  rotations; 
se  increases  have  been  slightly  more  than  lost  in  reduced 
et  result  to  date  being  an  average  loss  of  $2.53  per  acre 
g the  cost  of  the  potassium. 

hs  nearly  paid  its  cost  during  the  first  rotation,  and  has  sub- 
nnual  cost  and  about  100  percent  net  profit ; while  potassium, 
a general  average,  has  produced  no  effect,  and  money  spent  for  its  applica- 


Plate  3. — Clover  on  Urbana  Field,  South  Farm 
Crop  Eesidues  Plowed  Under 


1915 ] 


McLean  County 


13 


tion  has  been  lost.  These  field  results  are  in  harmony  with  what  might  well  be 
expected  on  land  naturally  containing  in  the  plowed  soil  of  an  acre  only  about 
1,200  pounds  of  phosphorus  and  more  than  36,000  pounds  of  potassium. 

The  total  value  of  five  average  crops  harvested  from  the  untreated  land  dur- 
ing the  last  four  years  is  $65.  Where  limestone  and  phosphorus  have  been  used 
together  with  organic  manures  (either  crop  residues  or  farm  manure),  the  cor- 
responding value  exceeds  $98.  Thus  200  acres  of  the  properly  treated  land 
would  produce  as  much  in  crops  and  in  value  as  300  acres  of  the  untreated  land. 

The  excessive  applications  on  Plot  10  have  usually  produced  rank  growth 
of  straw  and  stalk,  with  the  result  that  oats  have  often  lodged  badly  and  corn 
has  frequently  suffered  from  drouth  and  eared  poorly.  Wheat,  however,  has 
as  an  average  yielded  best  on  this  plot.  The  largest  yield  of  corn  on  Plot  10  was 
118  bushels  per  acre  in  1907. 

As  an  average  of  the  results  secured  during  the  twelve  years  1903  to  1914, 
on  the  University  South  Farm  where  fine-ground  raw  rock  phosphate  is  applied 
at  the  rate  of  500  pounds  per  acre  per  annum  on  the  typical  brown  silt  loam 
prairie  soil,  the  return  for  each  ton  of  phosphate1  used  has  been  $13.57  on  Series 


Plate  4. — Clover  on  Urbana  Field,  South  Farm 
Fine-Ground  Book  Phosphate  Plowed  Under  with  Crop 

‘During  the  first  four  years,  Series  100  received  only  1,500  pounds  per  acre  of  phos- 
phate, and  both  series  received  also  % ton  per  acre  of  limestone,  the  effect  of  which  probably 
would  be  slight,  as  may  be  judged  from  the  data  secured  later  and  reported  herein. 


14 


Soil  Report  No.  10 


[May, 


100  and  $12.07  on  Series  200,  with  the  “lower  prices”  allowed  for  produce,  the 
rotation  being  wheat,  corn,  oats,  and  clover  (or  soybeans).  This  gives  an  average 
return  of  $12.82  for  each  ton  of  phosphate  applied.  Averages  for  each  rotation 
period  show  the  following  value  of  increase  per  ton  of  phosphate  used : 


Lower  Higher 

prices  prices 

First  rotation,  1903  to  1906 $ 8.26  $11.80 

Second  rotation,  1907  to  1910 11.33  16.19 

Third  rotation,  1911  to  1914  18.88  26.97 


Thus  the  rock  phosphate  paid  back  more  than  its  cost  during  the  first  rota- 
tion, more  than  iy2  times  its  cost  during  the  second  rotation,  and  more  than  21/2 
times  its  cost  during  the  third  rotation  period. 

One  ton  of  fine-ground  rock  phosphate  costs  about  the  same  as  500  pounds  of 
steamed  bone  meal.  Altho  in  less  readily  available  form,  the  rock  phosphate  con- 
tains as  much  phosphorus,  ton  for  ton,  as  the  bone  meal ; and,  when  equal  money 
values  are  applied  in  connection  with  liberal  amounts  of  decaying  organic  matter, 
the  natural  rock  may  soon  give  as  good  results  as  the  bone, — and,  by  supplying 
about  four  times  as  much  phosphorus,  the  rock  provides  for  greater  durability. 

The  results  just  given  represent  averages  covering  the  residue  system  and 
the  live-stock  system,  both  of  which  are  represented  in  this  crop  rotation  on  the 
South  Farm. 

Ground  limestone  at  the  rate  of  8 tons  per  acre  was  applied  to  the  east  half 
of  these  series  of  plots  (excepting  the  check  plots,  which  receive  only  residues  or 
manure),  beginning  in  1910  on  Series  200  and  in  1911  on  Series  100.  Subsequent 
applications  are  made  of  2 tons  per  acre  each  four  years,  beginning  in  1914  on 
Series  200  and  in  1915  on  Series  100.  As  an  average  of  results  from  both  series, 
the  crop  values  were  increased  during  the  third  rotation,  1911-1914,  as  follows: 


Residue  System  Live-Stock  System 
Lower  Higher  Lower  Higher 
prices  prices  prices  prices 

Gain  for  phosphate  $18.80  $26.86  $18.96  $27.09 

Gain  for  limestone  2.31  3.30  2.55  3.64 


Detailed  records  of  these  investigations  are  given  in  Tables  5 and  6,  the  data 
being  reported  by  half-plots  after  1910-1911.  (Series  300  and  400,  which  are 
also  used  in  this  rotation,  are  located  in  part  upon  black  clay  loam  and  a heavy 
phase  of  brown  silt  loam.  See  discussion  under  “Black  Clay  Loam,”  page  26.) 

Results  of  Experiments  on  Sibley  Field 

Table  7 gives  the  results  obtained  during  twelve  years  from  the  Sibley  soil 
experiment  field  located  in  Ford  county  on  the  typical  brown  silt  loam  prairie 
of  the  Illinois  corn  belt. 

Previous  to  1902  this  land  had  been  cropped  with  corn  and  oats  for  many 
years  under  a system  of  tenant  farming,  and  the  soil  had  become  somewhat  defi- 
cient in  active  organic  matter.  While  phosphorus  was  the  limiting  element  of 
plant  food,  the  supply  of  nitrogen  becoming  available  annually  was  but  little  in 
excess  of  the  phosphorus,  as  is  well  shown  by  the  corn  yields  for  1903,  when  the 
addition  of  phosphorus  produced  an  increase  of  8 bushels,  nitrogen  produced 
no  increase,  but  nitrogen  and  phosphorus  increased  the  yield  by  15  bushels. 

After  six  years  of  additional  cropping,  however,  nitrogen  appeared  to  be- 


1915] 


McLean  County 


15 


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16 


Soil  Report  No.  10 


[May, 


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1915 ] 


McLean  County 


17 


come  the  most  limiting  element,  the  increase  in  the  corn  in  1907  being  9 bushels 
from  nitrogen  and  only  5 bushels  from  phosphorus,  while  both  together  pro- 
duced an  increase  of  33  bushels.  By  comparing  the  corn  yields  for  the  four 
years  1902,  1903,  1906,  and  1907,  it  will  be  seen  that  the  untreated  land  appar- 
ently grew  less  productive,  whereas,  on  land  receiving  both  phosphorus  and 
nitrogen,  the  yield  appreciably  increased,  so  that  in  1907,  when  the  untreated 
rotated  land  produced  only  34  bushels  of  corn  per  acre,  a yield  of  72  bushels 
(more  than  twice  as  much)  was  produced  where  lime,  nitrogen,  and  phosphorus 
had  been  applied,  altho  the  two  plots  produced  exactly  the  same  yield  (57.3 
bushels)  in  1902. 


Table  7. — Crop  Yields  in  Soil  Experiments,  Sibley  Field 


Brown  silt  loam  prairie ; 1 
early  Wisconsin 
glaciation 

Corn  Corn 
1902 ( 1903 

Oats 

1904 

! Wheat  Corn 
1905  1906 1 

Corn 

1907 

Oats 

1908 

Wheat1  Corn 
1909  1910 

Corn 

1911 

Oats 

1912 

Wheat 

1913 

Plot 

Soil  treatment 
applied 

Bushels  per  acre 

101 

None  

57.3 

50.4 

74.4 

29.5 

36.7 

33.9 

25.9 

25.3 

26.6 

20.7 

84.4 

5.5 

102 

Lime  

60.0 

54.0 

74.7 

31.7 

39.2 

38.9 

24.7 

28.8 

34.0 

22.2 

85.6 

6.8 

103 

Lime,  nitro 

60.0 

54.3 

~77\5 

32.8 

4L7 

48.1 

"36(3 

19(0 

297) 

"22(4 

25.3 

18.3 

104 

Lime,  phos 

61.3 

62.3 

92.5 

36.3 

44.8 

43.5 

25.6 

32.2 

52.0 

31.6 

92.3 

10.7 

105 

Lime,  potas 

56.0 

49.9 

74.4 

30.2 

37.5 

34.9 

22.2 

23.2 

34.2 

21.6 

83.1 

7.5 

106 

Lime,  nitro.,  phos. . . 

57.3 

"69Y 

88.4 

45.2 

"68(5 

72.3 

"4576 

“33X" 

"5576 

"35(3 

42.2 

24.7 

107 

Lime,  nitro.,  potas.. 

53.3 

51.4 

75.9 

37.7 

39.7 

51.1 

42.2 

25.8 

46.2 

20.1 

55.6 

19.2 

108 

Lime,  phos.,  potas.. . 

58.7 

60.9 

80.0 

39.8 

41.5 

39.8 

27.2 

28.5 

43.0 

31.8 

79.7 

11.8 

109 

Lime,  nitro.,  phos., 
potas 

58.7' 

65.9 

82.5 

48.0 

69.5 

80.1 

52.8 

35.0 

58.0 

35.7 

57.2 

24.5 

110 

Nitro.,  phos.,  potas.. 

60.0, 

60.1 

85.0 

48.5 

63.3 

72.3 

44.1 

30.8 

64.4 

31.5 

54.1 

18.0 

Increase : Bushels  per  Acre 


For  nitrogen 

.0 

.3 

2.8 

1.1 

2.5 

9.2;  11.6 

-9.8 

-5.0, 

.2 

-60.3 

11.5 

For  phosphorus  

1.3 

8.3 

17.8 

4.6 

5.6 

4.6  .9 

3.4 

18.0, 

9.4 

6.7 

3.9 

For  potassium  

-4.0, 

-4.1 

-.3 

-1.5 

-1.7 

-4.0 ! -2.5 

-5.6 

.2, 

-.6 

-2.5 

.7 

For  nitro.,  phos.  over 
phos 

-4.o : 

6.8 

-4.1 

8.9 

23.7 

28.8  20.0 

1.1 

3.6, 

3.7 

-50.1 

14.0 

For  phos.,  nitro.  over 
nitro  

-2.7 

14.8 

10.9 

12.4 

24.8 

24.2  9.3 

14.3 

20.6 

12.9 

10.9 

6.4 

For  potas.,  nitro.,  phos. 
over  nitro.,  phos 

1.4 

-3.2 

-5.9 

2.8 

1.0 

7.8  7.2 

1.7 

| 

2.4 

.4 

15.0 

-.2 

Value  of  Crops  per  Acre  in  Twelve  Years 


Plot 

Soil  treatment  applied 

Total  value  of 
twelve  crops 

Lower 

Higher 

prices 

prices 

101 

$172.89 

186.51 

$246.98 

266.45 

102 

103 

Lime,  nitrogen 

""177.44 

253.49 

104 

Lime,  phosphorus 

217.78 

311.11 

105 

Lime,  potassium 

167.32 

239.03 

106 

Lime,  nitrogen,  phosphorus 

246.91 

352.73 

107 

Lime,  nitrogen,  potassium 

198.16 

283.08 

108 

Lime,  phosphorus,  potassium 

204.90 

292.71 

109 

Lime,  nitrogen,  phosphorus,  potassium 

257.91 

368.45 

110 

Nitrogen,  phosphorus,  potassium 

242.47 

346.38 

Value  of  Increase  per  Acre  in  Twelve  Years 


For  nitrogen 

For  phosphorus 

For  nitrogen  and  phosphorus  over  phosphorus 

$ 9.07 
31.27 
29.13 

$12.96 

44.66 

41.62 

For  ‘phosphorus  and  nitrogen  over  nitrogen 

69.47 

99.24 

For  potassium,  nitrogen,  and  phosphorus  over  nitrogen  and  phosphorus 

11.00 

15.72 

18 


Soil  Report  No.  10 


[May, 


Even  in  the  unfavorable  season  of  1910  the  yield  of  the  highest  producing 
plot  exceeded  the  yield  of  the  same  plot  in  1902,  while  the  untreated  land  pro- 
duced less  than  half  as  much  as  it  produced  in  1902.  The  prolonged  drouth  of 
1911  resulted  in  almost  a failure  of  the  corn  crop,  but  nevertheless  the  effect  of 
soil  treatment  was  seen.  Phosphorus  appeared  to  be  the  first  limiting  element 
again  in  1909,  1910.  and  1911 ; while  the  lodging  of  oats,  especially  on  the  nitro- 
gen plots,  in  the  exceptionally  favorable  season  of  1912,  produced  very  irregular 
results.  In  1913,  wheat  averaged  6.6  bushels  without  nitrogen  or  phosphorus 
(Plots  101,  102,  105)  and  22.4  bushels  where  both  nitrogen  and  phosphorus  were 
added  (Plots  106,  109,  110). 

In  the  lower  part  of  Table  7 are  shown  the  total  values  per  acre  of  the  twelve 
crops  from  each  of  the  ten  different  plots,  the  amounts  varying  from  $167.32  to 
$257.91,  with  corn  valued  at  35  cents  a bushel,  oats  at  28  cents,  and  wheat  at 
70  cents.  Phosphorus  without  nitrogen  has  produced  $31.27  in  addition  to  the 
increase  by  lime,  but  with  nitrogen  it  has  produced  $69.47  above  the  crop  values 
where  only  lime  and  nitrogen  have  been  used.  The  results  show  that  in  26  cases 
out  of  48  the  addition  of  potassium  has  decreased  the  crop  yields.  Even  when 
applied  in  addition  to  phosphorus,  and  with  no  effort  to  liberate  potassium  from 
the  soil  by  adding  organic  matter,  potassium  has  produced  no  increase  in  crop 
values  as  an  average  of  the  results  from  Plots  108  and  109. 

By  comparing  Plots  101  and  102,  and  also  109  and  110,  it  is  seen  that  lime 
has  produced  an  average  increase  of  $14.53,  or  $1.21  an  acre  a year.  This  in- 
crease on  these  plots  is  practically  the  same  as  at  Urbana,  and  it  suggests  that  the 
time  is  here  when  limestone  must  be  applied  to  some  of  these  brown  silt  loam  soils. 

While  nitrogen,  on  the  whole,  has  produced  an  appreciable  increase,  espe- 
cially on  those  plots  to  which  phosphorus  has  also  been  added,  it  has  cost,  in  com- 
mercial form,  so  much  above  the  value  of  the  increase  produced  that  the  only 
conclusion  to  be  drawn,  if  we  are  to  utilize  this  fact  to  advantage,  is  that  the 
nitrogen  must  be  secured  from  the  air. 

Results  of  Experiments  on  Bloomington  Field 

Space  is  taken  to  insert  Tables  8 and  9,  giving  all  results  thus  far  obtained 
from  the  Bloomington  soil  experiment  field,  which  is  also  located  on  the  brown 
silt  loam  prairie  soil  of  the  Illinois  corn  belt.  This  field  is  a part  of  the  S.  Noble 
King  farm. 

The  general  results  of  the  thirteen  years’  work  tell  much  the  same  story  as 
those  from  the  Sibley  field.  The  rotations  have  differed  since  1905  by  the  use 
of  clover  and  the  discontinuing  of  the  use  of  commercial  nitrogen, — in  conse- 
quence of  which  phosphorus  without  commercial  nitrogen,  on  the  Bloomington 
field,  has  produced  an  even  larger  increase  ($99.85)  than  has  been  produced  by 
phosphorus  and  nitrogen  over  nitrogen  on  the  Sibley  field  ($69.47). 

It  should  be  stated  that  a draw  runs  near  Plot  110  on  the  Bloomington  field, 
that  the  crops  on  that  plot  are  sometimes  damaged  by  overflow  or  imperfect 
drainage,  and  that  Plot  101,  occupies  the  lowest  ground  on  the  opposite  side  of 
the  field.  In  part  because  of  these  irregularities  and  in  part  because  only  one 
small  application  has  been  made,  no  conclusions  can  be  drawn  in  regard  to  lime. 
Otherwise  all  results  reported  in  Table  8 are  considered  reliable.  They  not  only 


1915] 


McLean  County 


19 


furnish  much  information  in  themselves,  but  they  also  offer  instructive  com- 
parison with  the  Sibley  field. 

Wherever  nitrogen  has  been  provided,  either  by  direct  application  or  by  the 
use  of  legume  crops,  the  addition  of  the  element  phosphorus  has  produced  very 
marked  increases,  the  average  yearly  increase  for  the  Bloomington  field  being 
worth  $7.02  an  acre.  This  is  $4.52  above  the  cost  of  the  phosphorus  in  200  pounds 
of  steamed  bone  meal,  the  form  in  which  it  is  applied  on  the  Sibley  and  the 
Bloomington  fields.  On  the  other  hand,  the  use  of  phosphorus  without  nitrogen 
will  not  maintain  the  fertility  of  the  soil  (see  Plots  104  and  106,  Sibley  field). 
As  the  only  practical  and  profitable  method  of  supplying  nitrogen,  a liberal  use 
of  clover  or  other  legumes  is  suggested,  the  legume  to  be  plowed  under  either 
directly  or  as  manure,  preferably  in  connection  with  the  phosphorus  applied, 
especially  if  raw  rock  phosphate  is  used. 

Prom  the  soil  of  the  best  treated  plots  on  the  Bloomington  field,  180  pounds 
per  acre  of  phosphorus,  as  an  average,  has  been  removed  in  the  thirteen  crops. 
This  is  equal  to  15  percent  of  the  total  phosphorus  contained  in  the  surface  soil 
of  an  acre  of  the  untreated  land.  In  other  words,  if  such  crops  could  be  grown 
for  eight;,  years,  they  would  require  as  much  phosphorus  as  the  total  supply  in 
the  ordinary  plowed  soil.  The  results  plainly  show,  however,  that  without  the 
addition  of  phosphorus  such  crops  cannot  be  grown  year  after  year.  Where 
no  phosphorus  has  been  applied,  the  crops  have  removed  only  120  pounds  of 
phosphorus  in  the  thirteen  years,  which  is  equivalent  to  only  10  percent  of  the 
total  amount  (1,200  pounds)  present  in  the  surface  soil  at  the  beginning  of  the 
experiment  in  1902.  The  total  phosphorus  applied  from  1902  to  1914,  as  an 
average  of  all  plots  where  it  has  been  used,  has  amounted  to  325  pounds  per  acre 
and  has  cost  $32.50. 1 This  has  paid  back  $97.20,  or  300  percent  on  the  invest- 


Plate  5. — Corn  in  1912  on  Bloomington  Field 
On  Left,  Residues,  Lime,  and  Potassium:  Yield,  58.9  Bushels 
On  Right,  Residues,  Lime,  and  Phosphorus:  Yield,  86.1  Bushels 


1This  is  based  on  $25  a ton  for  steamed  bone  meal,  but  in  recent  years  the  price  has  been 
advanced  generally  to  nearly  $30. 


20 


Soil  Report  No.  10 


[May, 


It 


II 


I1|S1S|333|S3 


31 

37.5 

44.1 

32.1 
~50A~ 

34.5 
J9^ 

is 

55.2 

47.9 

ass|ass 

S3 

33 

Ife  53 

131 

rtH  O 

§3 

1.56  | 
1.09 

ga 

g5 

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3l|31i 

111 

si 

S3' 

131 

m 

is 

iass|sss 

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S3| 

cc 

30.8  , 

28.8 

io  oq  cq 
Snn 

05  WOO 

taa 

io  10 

Si 

SSI 

Mi 

S3 

05  CO 
8§ 

lOO^ 

m 

13 

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m 

31 

23333^ 

CO  CO  Oi  CO  CO  h- 

ag^g* 

2s-  !f 

ar^a 

■ 1.2 

19.0 

1.0 

-3.2 

14.6 

9.5 

-.12 
1.07 
-.07 
-1.65 
-.46 
| .00 

10.4 
4.4 

11.7 

20.4 

l 1.0 

O C5  N CO  W N 

' -.8 
12.7 
-3.9 
4.6 
18.1 
3.3 

^■aaa 

1915 ] 


McLean  County 


21 


Table  9. — Value  op  Crops  per  Acre  in  Thirteen  Years,  Bloomington  Field 


Plot 

Soil  treatment  applied 

Total  \ 
thirtee: 
Lower 
prices 

ralue  of 
n crops 
Higher 
prices 

101 

102 

$186.83 

186.76 

$266.90 

266.80 

103 

104 

105 

193.83 

286.61 

190.53 

276.90 

409.45 

272.19 

Lime,  phosphorus 

Lime,  potassium 

106 

107 

108 

Lime,  residues,  phosphorus 

285.03 

191.10 

294.91 

407.19 

273.00 

421.31 

Lime,  residues,  potassium 

Lime,  phosphorus,  potassium 

109 

110 

Lime,  residues,  phosphorus,  potassium 

Residues,  phosphorus,  potassium 

284.47 

259.10 

406.39 

370.15 

Value  of  Increase  per  Acre  in  Thirteen  Years 

For  re 
For  pi 
For  re 
For  pi 
For  pi 

$ 7.07 
99.85 
-1.58 
91.20 
-.56 

$ 10.10 
142.65 
-2.26 
130.29 
-.80 

losphorus 

sidues  and  phosphorus  over  phosphorus 

vosphorus  and  residues  over  residues 

itassium,  residues,  and  phosphorus  over  residues  and  phosphorus. . . . 

ment ; whereas  potassium,  used  in  the  same  number  of  tests  and  at  the  same  cost, 
has  paid  back  only  $2.20  per  acre  in  the  thirteen  years,  or  less  than  7 percent 
of  its  cost.  Are  not  these  results  to  be  expected  from  the  composition  of  such 
soil  and  the  requirements  of  crops?  (See  Table  2 ; also  Table  A in  the  Appendix.) 

Nitrogen  was  applied  to  this  field,  in  commercial  form  only,  from  1902  to 
1905 ; but  clover  was  grown  in  1906  and  1910,  and  a cover  crop  of  cowpeas  after 
the  clover  in  1906.  The  cowpeas  were  plowed  under  on  all  plots,  and  the  1910 
clover  (except  the  seed)  was  plowed  under  on  five  plots  (103,  106,  107,  109,  and 
110).  Straw  and  corn  stalks  have  also  been  returned  to  these  plots  in  recent 
years.  The  effect  of  returning  these  residues  to  the  soil  has  been  appreciable  since 
1910  (an  average  increase  on  Plots  106  and  109  of  4.5  bushels  of  wheat,  5.4  bushels 
of  corn,  and  4.3  bushels  of  oats)  and  probably  will  be  more  marked  on  subse- 
quent crops.  Indeed,  the  large  crops  of  corn,  oats,  and  wheat  grown  on  Plots 
104  and  108  during  the  thirteen  years  have  drawn  their  nitrogen  very  largely 
, from  the  natural  supply  in  the  organic  matter  of  the  soil.  The  roots  and  stubble 
of  clover  contain  no  more  nitrogen  than  the  entire  plant  takes  from  the  soil 
alone,  but  they  decay  rapidly  in  contact  with  the  soil  and  probably  hasten  the 
decomposition  of  the  soil  humus  and  the  consequent  liberation  of  the  soil  nitro- 
gen. But  of  course  there  is  a limit  to  the  reserve  stock  of  humus  and  nitrogen 
remaining  in  the  soil,  and  the  future  years  will  undoubtedly  witness  a gradually 
increasing  difference  between  Plots  104  and  106,  and  between  Plots  108  and  109, 
in  the  yields  of  grain  crops. 

Plate  6 shows  graphically  the  relative  values  of  the  thirteen  crops  for  the 
eight  comparable  plots,  Nos.  102  to  109.  The  cost  of  the  phosphorus  is  indicated 
by  that  part  of  the  diagram  above  the  short  crossbars.  It  should  be  kept  in 
mind  that  no  value  is  assigned  to  clover  plowed  under  except  as  it  reappears  in 
the  increase  of  subsequent  crops.  Plots  106  and  109  are  heavily  handicapped 
because  of  the  clover  failure  on  those  plots  in  1906  and  the  poor  yield  of  clover 
seed  in  1910,  whereas  Plots  104  and  108  produced  a fair  crop  in  1906  and  a very 


Soil  Report  No.  10 


[May, 


22 


large  crop  in  1910.  Plot  106,  which  receives  the  most  practical  treatment  for 
permanent  agriculture  (RLP),  has  produced  a total  value  in  thirteen  years  only 
$1.58  below  that  from  Plot  104  (LP).  (See  also  table  on  last  page  of  cover.) 

The  Subsurface  and  Subsoil 

In  Tables  10  and  11  are  recorded  the  amounts  of  plant  food  in  the  subsur- 
face and  the  subsoil  of  the  different  types  of  soil  in  McLean  county,  but  it  should 
be  remembered  that  these  supplies  are  of  little  value  unless  the  top  soil  is  kept 
rich.  Probably  the  most  important  information  contained  in  these  tables  is 
that  the  most  common  prairie  soil  and  the  upland  timber  soils  are  from  slightly  to 
strongly  acid  in  the  subsurface  and  sometimes  contain  no  limestone  in  the  subsoil. 
This  fact  emphasizes  the  importance  of  having  plenty  of  limestone  in  the  surface 
soil  to  neutralize  the  acid  moisture  which  rises  from  the  lower  strata  by  capillary 
action  during  times  of  partial  drouth,  which  are  critical  periods  in  the  life  of 
such  plants  as  clover.  While  the  common  brown  silt  loam  prairie  is  usually 
slightly  acid,  the  upland  timber  soils  are,  as  a rule,  more  distinctly  in  need  of 


$186.76  $193.83  $286.61  $190.53  $285.03  $191.10  $294.91  $284.47 


Plate  6. — Crop  Values  for  Thirteen  Years,  Bloomington  Experiment  Field 
(R=residues;  P=phosphorus ; K=potassium,  or  kalium) 


1915  J 


McLean  County 


23 


limestone,  and  as  already  explained,  they  are  also  more  deficient  in  organic  mat- 
ter and  nitrogen  than  the  prairie  soils,  and  thus  more  in  need  of  growing  clover. 


Table  10. — Fertility  in  the  Soils  of  McLean  County,  Illinois 
Average  pounds  per  acre  in  4 million  pounds  of  subsurface  soil  (about  6%  to  20  inches) 


Soil 

Total 

Total 

Total 

Total 

Total 

Total 

Lime- 

Soil 

type 

Soil  type 

organic 

nitro- 

phos- 

potas- 

magne- 

cal- 

stone 

acid- 

No. 

carbon 

gen 

phorus 

sium 

sium 

cium 

present 

ity 

Upland  Prairie  Soils 


1126 

Brown  silt  loam  

74  530 

6 660 

1 870 

73  230 

19  520 

17  850 

110 

1120 

Black  clay  loam  

91  ISO 

8 130 

3 150 

70  760 

33  150 

57  190 

Often 

Barely 

1120.2 

Gravelly  black  clay  loam 

65  200 

6 240 

2 600 

67  880 

46  640 

106  200 

252  200 

1128 

Brown-gray  silt  loam  oe 

tight  clay 

27  720 

3 200 

2 160 

78  960 

17  640 

12  040 

880 

1190 

Gravelly  loam  ... 

58  160 

5 600 

2 000 

75  840 

20  400 

15  080 

40 

Upland  Timber  Soils 


1134 

Yellow-gray  silt  loam  . . . 

24  490 

2 710 

1 490  74  230  16  390 

13  980 

2 350 

1135 

Yellow  silt  loam  ...... 

15  280 

2 020 

1 540  |72  000  24  620 

14  620 

| 3 660 

Terrace  Soils 


Brown  silt  loam  over 

gravel  

68  200 

6 320; 

2 160 

75  880 

18  960 

12  840 

80 

Brown  silt  loam  on  gravel 

55  320 

5 160 

1 640 

83  780 

22  600 

14  340 

100 

Yellow-gray  silt  loam  on 

gravel  

26  800 

3 000 

1 560 

73  800 

19  440 

17  240 

80 

Swamp  and  Bottom-Land  Soils 


1401 

Deep  peat 

608  090 

52  420 

4 610 

14  160 

11  080 

63  270 

Barely 

Often 

1426 

Deep  brown  silt  loam . . . 

144  760 

11  520 

3 320 

69  280 

22  080 

34  920 

1 300 

1454 

Mixed  loam  

112  560 

11  080 

3 080 

83  320 

28  960 

37  000 

3 160 

Table  11. — Fertility  in  the  Soils  of  McLean  County,  Illinois 
Average  pounds  per  acre  in  6 million  pounds  of  subsoil  (about  20  to  40  inches) 


Soil 

l'otal 

Total 

Total 

Total 

Total 

Total 

Lime- 

Soil 

type 

Soil  type 

organic 

nitro- 

phos- 

potas- 

magne- 

cal- 

stone 

acid- 

No. 

carbon 

gen 

phorus 

sium 

sium 

cium 

present 

ity 

Upland  Prairie  Soils 


1126 

Brown  silt  loam  

32  310 

3 620 

2 350 

114  870 

48  600 

46  360 

Barely 

Often 

1120 

Black  clay  loam 

35  480 

3 450 

3 410 

111  560 

58  820 

80  450 

Often 

Barely 

1120.2 

Gravelly  black  clay  loam 

47  760 

4 140 

3 120 

104  220 

54  540 

119  520 

279  300 

1128 

Brown-gray  silt  loam  on 

tight  clay  

21  900 

3 120 

3 540 

120  600 

36  240 

19  500 

840 

1190 

Gravelly  loam  

57  060 

5 460 

2 040 

110  040 

32  100 

19  560 

60 

Upland  Timber  Soils 


1134 

Yellow-gray  silt  loam... 

21  380 

2 840 

4 040 

114  270142  060 

31  590 1 1 Often 

1135 

Yellow  silt  loam 

20  250 

2 580 

3 000 

110  82o| 58  650 

60  510 1 | Often 

Terrace  Soils 


1527 

Brown  silt  loam  over 

gravel  

36  120 

3 840 

2 520 

106  800 

39  540 

22  320 

420 

1526.2 

Brown  silt  loam  on  gravel 

42  690 

4 470 

2 130 

113  040 

37  380 

24  300 

Often 

1534.4 

Yellow-gray  silt  loam  on 

gravel  

28  800 

3 180 

2 700 

103  620 

30  360 

27  180 

420 

Swamp  and  Bottom-Land  Soils 

1401 

Deep  peat 

752  400 

55  050 

4 650 

38  010 

20  490 

71  910 

30 

1426 

Deep  brown  silt  loam .... 

86  880 

5 640 

3 180 

108  600 

27  720 

47  220 

120 

1454 

Mixed  loam  

101  280 

9 900 

3 120 

123  900 

43  320 

49  200 

60 

24 


Soil  Report  No.  10 


[May, 


INDIVIDUAL  SOIL  TYPES 
(a)  Upland  Prairie  Soils 

The  upland  prairie  soils  of  McLean  county  occupy  1,022.68  square  miles,  or 
87.64  percent  of  the  entire  area  of  the  county.  They  are  black  or  brown  in  color, 
owing  to  their  large  content  of  organic  matter. 

The  accumulation  of  organic  matter  in  the  prairie  soils  is  due  to  the  growth 
of  prairie  grasses  whose  network  of  roots  was  protected  from  complete  decay  by 
imperfect  aeration  due  to  the  covering  of  fine  soil  material  and  the  moisture  it 
contained.  On  the  native  prairies,  the  tops  of  these  grasses  were  usually  burned 
or  became  almost  completely  decayed.  From  a sample  of  virgin  sod  of  “blue 
stem,”  one  of  the  most  common  prairie  grasses,  it  has  been  determined  that  an 
acre  of  this  soil  to  a depth  of  seven  inches  contained  13.5  tons  of  roots.  Many  of 
these  roots  died  each  year  and  by  partial  decay  formed  the  humus  of  these  dark 
prairie  soils. 

Brown  Silt  Loam  (1126,  or  926  on  moraines ) 

Brown  silt  loam  is  the  most  important  as  well  as  the  most  extensive  soil  type 
in  the  county.  It  covers  an  area  of  847.38  square  miles  (542,323  acres),  or  72.6 
percent  of  the  entire  county. 

This  type  occupies  the  slightly  undulating  to  rolling  areas  of  the  prairie 
land,  much  of  which  is  well  surface-drained,  while  many  areas  need  artificial 
drainage.  The  morainal  areas  are  sometimes  sufficiently  rolling  to  require  con- 
siderable care  in  preventing  erosion.  Altho  brown  silt  loam  is  normally  a prairie 
soil,  yet  in  some  limited  areas  forests  have  recently  invaded  the  dark  soil.  These 
forests  consist  quite  largely  of  black  walnut,  wild  cherry,  hackberry,  ash,  hard 
maple,  and  elm.  A black-walnut  soil  is  recognized  generally  by  farmers  as  being 
one  of  the  best  timber  soils  because  of  the  fact  that  it  still  contains  a large 
amount  of  organic  matter,  characteristic  of  prairie  soils.  After  the  growth  of 
several  generations  of  trees,  the  organic  matter  would  become  so  reduced  that 
the  soil  would  then  be  classed  as  a timber  type. 

The  surface  soil,  0 to  6%  inches,  is  a brown  silt  loam,  varying  on  the  one 
hand  to  black  as  it  grades  into  black  clay  loam  (1120),  and  on  the  other  hand  to 
grayish  brown  or  yellowish  brown  as  it  grades  into  the  timber  type,  yellow-gray 
silt  loam  (1134  or  934).  The  physical  composition  varies  to  some  extent,  but  it 
is  normally  a silt  loam,  containing  from  65  to  80  percent  of  silt,  together  with 
some  sand,  and  from  10  to  15  percent  of  clay.  The  amount  of  clay  increases  as 
the  type  approaches  the  black  clay  loam  (1120),  and  becomes  greatest  in  the 
level,  poorly  drained  areas.  The  amount  of  sand  varies  from  10  to  20  percent. 

The  organic-matter  content  varies  from  3.5  to  6.6  percent,  with  an  average 
of  4.9  percent,  or  49  tons  per  acre.  The  amount  is  less  in  the  more  rolling  areas 
than  in  the  low  and  poorly  drained  parts,  owing  to  the  fact  not  only  that  less 
vegetation  grows  on  the  drier,  rolling  areas,  but  that  when  incorporated  with  the 
soil  much  of  it  is  removed  by  erosion  and  undergoes  greater  decomposition  be- 
cause of  better  aeration  and  less  moisture.  Where  the  type  passes  into  the  yel- 
low-gray silt  loam  (1134  or  934),  the  organic-matter  content  becomes  less,  while 
in  the  low,  swampy  tracts  where  the  grasses  grew  more  luxuriantly  and  their 


1915] 


McLean  Count? 


25 


roots  were  more  abundant,  the  large  moisture  content  furnished  conditions  more 
favorable  for  the  preservation  of  organic  matter. 

The  natural  subsurface  is  represented  by  a stratum  varying  from  6 to  16 
inches  in  thickness,  being  thinner  on  the  more  rolling  areas,  while  decidedly 
thicker  and  darker  on  the  more  level  areas.  Its  physical  composition  varies  in 
the  same  way  as  that  of  the  surface  soil,  but  it  usually  contains  a slightly  larger 
amount  of  clay,  especially  as  it  approaches  the  black  clay  loam  type  (1120). 
Both  color  and  depth  vary  with  the  topography,  the  stratum  being  lighter  in 
color  as  well  as  shallower  on  the  more  rolling  areas  and  where  the  type  grades 
into  yellow-gray  and  yellow  silt  loam  (1134  or  1135).  The  amount  of  organic 
matter  varies  with  depth,  but  the  average  for  this  stratum  (which  is  twice  the 
thickness  of  the  surface  soil  as  it  is  sampled)  is  3.2  percent,  or  64  tons  per  acre. 

The  natural  subsoil  begins  at  12  to  23  inches,  and  extends  to  an  indefinite 
depth,  but  is  sampled  to  40  inches.  It  varies  with  the  topography  both  in  color 
and  texture,  and  becomes  slightly  coarser  with  depth.  It  consists  of  a yellow  or 
drabbish  mottled  yellow,  clayey  silt  or  silty  clay,  plastic  when  wet.  Where  the 
drainage  has  been  good,  it  is  of  a bright  to  a pale  yellow  color.  With  poor  drain- 
age it  approaches  a drab  or  olive  color  with  pale  yellow  mottlings  or  a yellow 
color  with  mottlings  of  drab.  Each  of  the  above  strata  is  pervious  to  water,  so 
that  drainage  takes  place  with  little  difficulty. 

A phase  of  brown  silt  loam  has  been  recognized  in  this  county  where,  be- 
cause of  the  removal  of  part  of  the  fine  loessial  material  by  erosion,  the  glacial 
drift  is  encountered  less  than  30  inches  from  the  surface.  If  the  drift  is  quite 
compact,  as  is  occasionally  the  case,  this  gives  rise  to  a somewhat  inferior  subsoil, 
owing  to  its  less  pervious  character.  This  condition,  however,  does  not  occur  very 
generally  nor  over  large  areas,  since  most  of  the  drift  is  pervious  and  some  is 
quite  gravelly.  This  phase  is  found  mostly  in  Township  23  North,  Range  6 East. 

In  the  northeastern  part  of  the  county  a slightly  sandy  phase  of  the  type  is 
found,  but  it  is  not  sufficiently  sandy  to  be  classed  as  a loam.  Small  areas  of 
sandy  and  gravelly  loam,  too  small  to  be  shown  on  the  map,  are  common  in  the 
most  rolling  part  of  the  morainal  regions. 

An  abnormal  phase  of  brown  silt  loam  about  30  acres  in  extent  is  found  in 
the  northeast  forty  of  Section  11,  Township  22  North,  Range  5 East.  In  spots  this 
varies  a great  deal  from  the  true  type,  being  a sandy  peat  in  some  places,  a marly 
peat  in  others,  and  in  still  others  containing  large  amounts  of  brown  iron  oxid. 

While  the  common  brown  silt  loam  is  in  fair  physical  condition,  yet  continu- 
ous cropping  to  corn,  or  corn  and  oats,  with  the  burning  of  the  stalks,  is  de- 
stroying the  tilth ; the  soil  is  becoming  more  difficult  to  work ; it  runs  together 
more ; and  aeration,  granulation,  and  absorption  of  moisture  do  not  take  place  as 
readily  as  formerly.  This  condition  of  poor  tilth  may  become  serious  if  the  pres- 
ent methods  of  management  continue ; it  is  already  one  of  the  factors  that  limit 
the  crop  yields.  The  remedy  is  to  increase  the  organic-matter  content  by  plow- 
ing under  farm  manure  and  crop  residues,  such  as  corn  stalks,  straw,  and  clover. 

The  addition  of  fresh  organic  matter  is  not  only  of  great  value  in  improving 
the  physical  condition  of  this  type  of  soil,  but  it  is  of  even  greater  importance 
because  of  its  nitrogen  content  and  because  of  its  power,  as  it  decays,  to  liberate 
potassium  from  the  inexhaustible  supply  in  the  soil,  and  phosphorus  from  the 
phosphate  contained  in  or  applied  to  the  soil. 


Soil  Reiokt  No.  10 


[May, 


26 

For  permanent,  profitable  systems  of  farming  on  brown  silt  loam,  phos- 
phorus should  be  applied  liberally,  and  sufficient  organic  matter  should  be  pro- 
vided to  furnish  the  necessary  amount  of  nitrogen.  On  the  ordinary  type,  lime- 
stone is  already  becoming  deficient.  An  application  of  two  tons  of  limestone  and 
one-half  ton  of  fine-ground  rock  phosphate  per  acre  every  four  years,  with  the 
return  to  the  soil  of  all  manure  made  from  a rotation  of  corn,  corn,  oats,  and 
clover,  will  maintain  the  fertility  of  this  type,  altho  heavier  applications  of  phos- 
phate may  well  be  made  during  the  first  two  or  three  rotations.  If  grain  farming 
is  practiced,  the  rotation  may  be  wheat,  corn,  oats,  and  clover,  with  an  extra  seed- 
ing of  clover  as  a cover  crop  in  the  wheat,  to  be  plowed  under  late  in  the  fall  or 
in  the  following  spring  for  corn ; and  most  of  the  crop  residues,  with  all  clover 
except  the  seed,  should  also  be  plowed  under.  In  either  system,  alfalfa  may  be 
grown  on  a fifth  field  and  moved  every  five  years,  the  hay  being  fed  or  sold.  In 
live-stock  farming  the  regular  rotation  may  be  extended  to  five  or  six  years  by 
seeding  both  timothy  and  clover  with  the  oats,  and  pasturing  one  or  two  years. 
Alsike  and  sweet  clover  may  well  replace  red  clover  at  times,  in  order  to  avoid 
clover  sickness.  (For  results  of  field  experiments  on  the  brown  silt  loam  prairie, 
see  Tables  3 to  9.) 

Black  Clay  Loam  (1120) 

Black  clay  loam  represents  the  flat  prairie  and  is  sometimes  called  “gumbo” 
because  of  its  sticky  character.  Its  formation  in  flatter,  poorly  drained  areas  is 
due  to  the  accumulation  of  organic  matter  and  to  the  washing  in  of  clay  and  fine 
silt  from  the  slightly  higher  adjoining  lands.  This  type  occupies  168.69  square 
miles  (17,961  acres) , or  14.47  percent  of  the  entire  area  of  the  county.  It  is  so  flat 
that  proper  drainage  is  one  of  the  most  difficult  problems  in  its  management. 

The  surface  soil,  0 to  6%  inches,  is  a black  granular  clay  loam,  varying  lo- 
cally to  a black  clayey  silt  loam  on  the  large  flat  areas.  It  contains,  on  an  aver- 
age, 7.6  percent  of  organic  matter,  or  76  tons  per  acre,  varying  from  65  to  98 
tons.  In  physical  composition  it  varies  somewhat  as  it  grades  into  other  types. 
As  it  passes  toward  the  brown  silt  loam,  which  nearly  always  surrounds  it,  it  be- 
comes more  silty.  Where  it  merges  into  the  gravelly  black  clay  loam  (1120.2),  it 
sometimes  contains  considerable  quantities  of  sand  and  fine  or  medium  gravel. 

The  subsurface  stratum  has  a thickness  of  10  to  16  inches  and  varies  from  a 
black  to  a brownish  gray  clay  loam,  usually  somewhat  heavier  than  the  surface 
soil.  The  average  amount  of  organic  matter  is  4 percent,  or  80  tons  per  acre. 
The  lower  part  of  this  stratum  frequently  is  a drab  or  yellowish  drab  silty  clay. 
The  stratum  is  quite  pervious  to  water,  owing  to  jointing  or  checking  from 
shrinkage  in  times  of  drouth. 

The  subsoil  to  a depth  of  40  inches  varies  from  a drab  to  a yellowish  drab 
silty  clay.  As  a rule,  the  iron  is  not  highly  oxidized,  because  of  poor  drainage 
and  lack  of  aeration.  Concretions  of  carbonate  of  lime  are  frequently  found.  The 
perviousness  of  the  subsoil  is  about  the  same  as  the  subsurface  and  is  due  to  the 
same  cause.  When  thrown  out  on  the  surface  where  wetting  and  drying  may 
take  place,  it  soon  breaks  into  small  cubical  masses.  Gravel  is  frequently  present. 

Black  clay  loam  presents  many  variations.  Here,  as  elsewhere,  the  boun- 
dary lines  between  it  and  the  brown  silt  loam  are  not  always  distinct.  In  some 
cases  topography  is  a great  help  in  locating  the  boundary,  but  in  other  cases  there 
may  be  an  intermediate  zone  of  greater  or  less  width.  The  washing  in  of  silty 


1915 ] 


McLean  County 


27 


material  from  the  surrounding  higher  lands,  especially  near  the  edges  of  the 
areas,  modifies  the  character  of  the  soil,  giving  the  surface  a silty  character.  This 
change  is  taking  place  more  rapidly  now,  with  the  annual  cultivation  of  the  soil, 
than  formerly,  when  washing  was  largely  prevented  by  prairie  grasses. 

Drainage  is  the  first  requirement  in  the  management  of  this  type ; altho  it 
usually  has  but  little  slope,  yet  because  of  its  perviousness  it  is  easily  tile-drained. 
Keeping  the  soil  in  good  physical  condition  is  very  essential,  and  thoro  drainage 
helps  to  do  this  to  a great  extent.  As  the  organic  matter  is  destroyed  by  cultiva- 
tion and  nitrification,  and  as  the  limestone  is  removed  by  cropping  and  leaching, 
the  physical  condition  of  the  soil  becomes  poorer,  and  as  a consequence  it  becomes 
more  difficult  to  work.  Both  organic  matter  and  limestone  tend  to  develop  granu- 
lation. The  former  should  be  maintained  by  turning  under  manure  or  such 
crop  residues  as  corn  stalks  and  straw,  and  by  the  use  of  clover  and  pasture  in 
rotations.  Ground  limestone  should  be  applied  when  needed  to  keep  the  soil 
sweet.  It  should  be  remembered  that  the  difficulty  of  working  clay  soils  is  in  pro- 
portion to  their  deficiency  in  organic  matter. 

While  black  clay  loam  is  one  of  the  best  soils  in  the  state,  yet  the  clay  and 
humus  which  it  contains  give  it  the  property  of  shrinkage  and  expansion  to  such  a 
degree  as  to  be  somewhat  objectionable  at  times,  especially  during  drouth.  When 
the  soil  is  wet,  these  constituents  expand,  and  when  the  moisture  evaporates  or  is. 
used  by  crops,  they  shrink.  This  results  in  the  formation  of  cracks,  sometimes  as 
much  as  two  or  more  inches  in  width  and  extending  with  lessening  width  to  two 
or  three  feet  in  depth.  During  the  drouth  of  1914,  the  cracks  were  so  large  and 
deep  that  in  many  cases  a one-inch  auger. could  be  forced  into  them,  without  turn- 
ing, to  a depth  of  more  than  two  feet.  These  cracks  allow  the  soil  strata  to  dry 
out  rapidly,  and  as  a result  the  crop  is  injured  thru  lack  of  moisture.  They 
may  do  considerable  damage  by  “blocking  out”  hills  of  corn  and  severing  the 
roots.  While  cracking  may  not  be  prevented  entirely,  good  tilth  with  a soil 
mulch  will  do  much  toward  that  end.  Both  for  aeration  and  for  producing  a 
mulch  for  conserving  moisture,  cultivation  is  more  essential  on  this  type  than 
on  the  brown  silt  loam.  It  must  be  remembered,  however,  that  cultivation  should 
be  as  shallow  as  possible,  in  order  to  prevent  injury  to  the  roots  of  the  corn. 

This  type  is  fairly  well  supplied  with  plant  food,  which  is  usually  liberated 
with  sufficient  rapidity  by  a good  rotation  and  by  the  addition  of  moderate 
amounts  of  organic  matter.  The  amount  of  organic  matter  added  must  be  in- 
creased, of  course,  with  continued  farming,  until  the  nitrogen  supplied  is  equal  to 
that  removed.  Altho  the  addition  of  phosphorus  is  not  expected  to  produce  marked 
profit,  it  is  likely  to  pay  its  cost  in  the  second  or  third  rotation ; and  even  by  main- 
taining the  productive  power  of  the  land,  the  capital  invested  is  protected. 

At  Urbana,  on  the  South  Farm  of  the  University  of  Illinois,  a series  of 
plots  devoted  chiefly  to  variety  tests  and  other  crop-production  experiments  ex- 
tends across  an  area  of  black  clay  loam.  Where  rock  phosphate  has  been  applied 
at  the  rate  of  500  pounds  an  acre  a year  in  connection  with  crop  residues,  in  a 
four-year  rotation  of  wheat,  corn,  oats,  and  clover  (or  soybeans),  the  value  of 
the  increase  produced  per  ton  of  phosphate  used  in  three  successive  rotation 
periods,  has  been  $2.13,  $4.70,  and  $6.48,  respectively,  at  the  “lower  prices,”  or 
$3.04,  $6.71,  and  $9.26,  respectively,  at  the  “higher  prices”  for  produce.  In  the 
live-stock  system,  the  phosphorus  naturally  supplied  in  the  manure,  supple- 


28 


Soil  Report  No.  10 


[May, 


merited  by  that  liberated  from  this  fertile  soil,  has  thus  far  been  nearly  suffi- 
cient to  meet  the  crop  requirements ; the  increase  in  crop  values  per  ton  of  phos- 
phate applied  having  been,  as  an  average  for  the  twelve  years,  only  $2.26  at 
the  ‘ ‘ lower  prices,  ’ ’ or  $3.26  at  the  ‘ ‘ higher  prices.  ’ ’ These  returns  are  less  than 
half  the  cost  of  the  phosphorus  applied,  and  some  seasons  no  benefit  appears. 

This  type  is  rich  in  magnesium  and  calcium,  and  in  the  Wisconsin  glacia- 
tion it  usually  contains  plenty  of  carbonates.  With  continued  cropping  and 
leaching,  applications  of  limestone  will  ultimately  be  needed. 

Gravelly  Black  Clay  Loam  (1120.2) 

Gravelly  black  clay  loam  occurs  in  the  poorly  drained  areas  in  the  eastern 
and  northeastern  part  of  the  county  in  the  large  sloughs  that,  during  parts  of 
the  year,  were  once  covered  with  streams  whose  currents  were  sufficiently  strong 
to  carry  and  deposit  considerable  quantities  of  sand  and  small  gravel.  These 
materials  have  become  mixed  with  the  fine  material  and  form  a distinct  phase  of 
black  clay  loam. 

The  surface  soil,  0 to  6%  inches,  varies  from  15  to  40  percent  in  the  amount 
of  gravel  it  contains,  the  gravel  itself  being  mostly  fine.  The  organic-matter 
content  is  not  quite  so  high  as  in  the  black  clay  loam,  being  about  6.4  percent,  or 
64  tons  per  acre. 

The  subsurface,  extending  from  6%  to  18  or  20  inches,  is  a brown  gravelly 
clay  loam,  containing  about  3.2  percent  of  organic  matter  and  passing  at  the 
lower  limit  into  a less  gravelly  and  much  lighter  colored  clay  loam. 

The  subsoil  varies  from  a drab  to  a pale  yellowish  drab,  indicating  poor 
oxidation.  It  does  not  usually  contain  as  much  gravel  as  either  the  surface  or 
subsurface.  Limestone  concretions  are  frequently  found. 

The  management  of  this  type  is  not  different  from  that  of  the  black  clay 
loam,  altho  there  may  be  a greater  necessity  for  maintaining  the  supply  of  or- 
ganic matter  because  of  the  lower  content  of  this  constituent  naturally  in  the 
soil.  The  presence  of  gravel  affects  the  working  of  the  soil  only  to  a slight  ex- 
tent, since  clay  possesses  such  distinctive  properties  that  it  takes  a large  amount 
of  gravel  and  sand  to  overcome  its  effects.  Hence  this  type  works  very  little 
differently  from  the  ordinary  black  clay  loam. 

Brown-Gray  Silt  Loam  on  Tight  Clay  (1128) 

Brown-gray  silt  loam  on  tight  clay  occurs  in  numerous  small  areas  thruout 
the  county,  principally  in  Township  23  North,  Ranges  1 West  and  1 East;  also  in 
the  southwestern  part  of  Township  24  North,  Range  1 West.  The  total  area  occu- 
pied by  this  type  is  2.42  square  miles  (1,549  acres),  or  .2  percent  of  the  area  of 
the  county.  While  not  of  great  importance  from  the  standpoint  of  area,  yet  it 
is  interesting  to  note  that  the  tight  clay  soils,  or  so-called  hardpan,  have  devel- 
oped under  certain  conditions  even  in  the  early  Wisconsin  glaciation.  The  top- 
ography is  flat  and  naturally  poorly  drained. 

The  surface  soil,  0 to  6%  inches,  consists  of  a brown  or  grayish  brown  silt 
loam,  containing  some  fine  sand  and  coarse  silt,  which  give  it  a peculiar,  mealy 
feel  but  excellent  texture.  It  contains  about  4 percent  of  organic  matter,  or  40 
tons  per  acre,  and  is  somewhat  richer  in  this  constituent  than  the  corresponding 


1915] 


McLean  County 


29 


type  in  southern  Illinois.  The  organic-matter  content  varies  with  its  relation  to 
other  types,  being  greater  where  it  approaches  brown  silt  loam  (1126)  and  less 
where  it  passes  into  yellow-gray  silt  loam  (1134).  As  a rule,  the  surface  soil  is 
not  so  granular  as  the  ordinary  brown  silt  loam. 

The  subsurface  is  represented  by  a stratum  10  to  12  inches  thick.  The  color 
varies  from  a brown  to  a gray  or  grayish  brown,  the  upper  part  of  the  stratum 
usually  being  brown,  while  the  lower  part  is  decidedly  gray  or  grayish  brown. 
It  differs  from  the  surface  soil  principally  in  the  amount  of  organic  matter  it 
contains,  having  1.2  percent  as  compared  with  4 percent  in  the  top  stratum. 

The  natural  subsoil  begins  at  a depth  of  16  to  18  inches,  as  a yellowish, 
almost  impervious,  silty  clay,  and  has  a thickness  of  10  to  15  inches.  It  is  usually 
underlain  by  a rather  pervious  silt.  This  tight  clay  layer  obstructs  drainage  to 
such  an  extent  that  percolation  is  not  very  rapid,  hence  the  soil  dries  very  slowly. 
The  land  should  be  tiled  thoroly,  unless  surface  drainage  is  sufficient.  In  order 
to  do  this,  the  lines  of  tile  should  be  placed  not  over  four  rods  apart. 

Care  should  be  taken,  on  this  type,  to  maintain  or  increase  the  amount  of  or- 
ganic matter  by  the  proper  rotation  of  crops  and  the  turning  under  of  crop  resi- 
dues and  farm  manures.  Deep-rooting  crops,  such  as  red,  mammoth,  and  sweet 
clover,  should  be  grown  so  as  to  render  the  tight  clay  more  permeable  to  air  and 
water. 

From  Table  2 it  will  be  seen  that  the  surface  soil  contains  only  4,200  pounds 
of  nitrogen  and  1,380  pounds  of  phosphorus  per  acre.  To  increase  these  amounts, 
liberal  applications  of  fine-ground  rock  phosphate  should  be  made  in  connection 
with  decaying  organic  matter,  as  on  the  brown  silt  loam.  This  type  is  distinctly 
acid  in  surface,  subsurface,  and  subsoil.  Limestone  should  be  applied  at  the  rate 
of  2 to  3 tons  per  acre  every  four  to  six  years.  The  initial  applications  may  well 
be  1 ton  of  phosphate  and  4 tons  of  limestone. 

Gravelly  Loam  (1190  or  990) 

Gravelly  loam  occupies  many  areas  on  the  upland  but  covers  a total  of  only 
96  acres.  These  areas  are  small  and  isolated,  representing  small  gravel  ridges  re- 
cently covered  by  fine  wind-blown  material. 

The  organic  matter  of  the  soil  should  be  maintained,  and  in  other  respects 
the  treatment  should  be  the  same  as  for  the  brown  silt  loam,  except  that  phos- 
phorus need  not  be  added,  because  of  the  deep  feeding  range  afforded  plant  roots. 

(b)  Upland  Timber  Soils 

The  upland  timber  soils  occur  along  streams,  or,  in  some  cases,  on  or  near 
somewhat  steep  morainal  ridges.  They  are  characterized  by  a yellow,  yellowish 
gray,  or  gray  color,  due  to  their  low  organic-matter  content.  This  lack  of  or- 
ganic matter  has  been  caused  by  the  long-continued  growth  of  forest  trees.  As 
the  forests  invaded  the  prairies,  two  effects  were  produced:  (1)  the  shading  of 
the  trees  prevented  the  growth  of  prairie  grasses,  the  roots  of  which  are  mainly 
responsible  for  the  large  amount  of  organic  matter  in  prairie  soils;  (2)  the  trees 
themselves  added  very  little  organic  matter  to  the  soil,  for  the  leaves  and  branches 
either  decayed  completely  or  were  burned  by  forest  fires.  As  a result  the  or- 
ganic-matter content  of  the  upland  timber  soils  has  been  reduced  until  in  some 
parts  of  the  state  a low  condition  of  apparent  equilibrium  has  been  reached. 


30 


Soil  Report  No.  10 


[May, 


Yellow-Gray  Silt  Loam  (1134  or  934) 

Yellow-gray  silt  loam  occurs  in  the  outer  timber  belts  along  streams  and  in 
the  less  rolling  of  the  timbered  morainal  areas.  The  type  covers  73.42  square 
miles  (46,989  acres),  or  6.23  percent  of  the  entire  area  of  the  county.  In  top- 
ography it  is  sufficiently  rolling  for  good  surface  drainage,  without  much  ten- 
dency to  wash  if  proper  care  is  taken. 

The  surface  soil,  0 to  6%  inches,  is  a yellow,  yellowish  gray,  gray,  or  brown- 
ish gray  silt  loam,  incoherent  but  not  granular.  The  more  nearly  level  areas  are 
gray  in  color,  while  the  more  rolling  phase  of  the  type  has  a yellow  or  brownish 
yellow  color.  As  the  type  approaches  the  brown  silt  loam,  it  becomes  decidedly 
darker.  The  organic-matter  content  averages  2.9  percent,  or  29  tons  per  acre, 
but  it  varies  considerably  with  topography.  As  the  type  approaches  the  brown 
silt  loam,  the  organic  matter  amounts  to  as  much  as  3.8  percent,  while  as  it  ap- 
proaches the  yellow  silt  loam,  it  diminishes  to  as  low  as  2.3  percent.  In  some 
cases  it  is  extremely  difficult  to  draw  the  line  between  the  long-cultivated  brown 
silt  loam  and  the  yellow-gray  silt  loam,  because  of  the  gradation  between  the  types. 

The  subsurface  stratum  varies  from  3 to  10  inches  in  thickness,  erosion  hav- 
ing reduced  its  thickness  on  the  more  rolling  areas.  It  is  usually  a gray,  grayish 
yellow,  or  yellow  silt  loam,  somewhat  pulverulent,  but  becoming  more  coherent 
and  plastic  with  depth.  The  amount  of  organic  matter  is  about  1 percent,  or  20 
tons  per  acre  in  the  four  million  pounds  of  soil. 

The  subsoil  is  a yellow  or  mottled  grayish  yellow,  clayey  silt  or  silty  clay, 
somewhat  plastic  when  wet,  but  friable  when  only  moist,  and  pervious  to  water. 
Glacial  drift  is  sometimes  encountered  at  a depth  of  less  than  40  inches.  This  is 
due  to  the  removal  by  erosion  of  part  of  the  loessial  material.  The  glacial  drift 
may  be  locally  a very  gravelly  deposit,  but  usually  it  is  a slightly  gravelly  clay 
and  in  some  places  is  lacking  in  permeability.  Otherwise,  each  stratum  of  this 
type  is  quite  pervious  to  water,  except  in  the  level  gray  areas,  where  the  tight 
and  more  or  less  compact  clayey  layer  has  been  formed  at  a depth  of  18  to  24 
inches.  Small  areas  of  light  gray  silt  loam  on  tight  clay  are  found  in  the  county, 
but  none  large  enough  to  be  shown  on  the  map. 

In  the  management  of  this  type  one  of  the  most  essential  things  is  the  main- 
taining or  the  increasing  of  organic  matter.  This  is  necessary  in  order  to  supply 
nitrogen  and  liberate  mineral  plant  food,  to  give  better  tilth,  to  prevent  ‘ ‘ running 
together,  ’ ’ and  on  some  of  the  more  rolling  phases,  to  prevent  washing. 

Another  essential  is  the  neutralization  of  the  acidity  of  the  soil  by  the  appli- 
cation of  ground  limestone,  so  that  clover,  alfalfa,  and  other  legumes  may  be 
grown  more  successfully.  The  initial  application  may  well  be  4 or  5 tons  per 
acre,  after  which  2 tons  per  acre  every  four  or  five  years  will  be  sufficient.  Since 
the  soil  is  poor  in  phosphorus,  this  element  should  be  applied,  preferably  in  con- 
nection with  farm  manure  or  clover  plowed  under.  In  permanent  systems  of 
farming,  fine-ground  natural  rock  phosphate  will  be  found  the  most  economical 
form  in  which  to  supply  the  phosphorus,  altho  steamed  bone  meal  or  acid  phos- 
phate may  well  be  used  temporarily  until  plenty  of  decaying  organic  matter  can 
be  provided. 

For  definite  results  from  the  most  practical  field  experiments  upon  typical 
yellow-gray  silt  loam,  we  must  go  down  into  ‘ ‘ Egypt,  ’ ’ where  the  people  of  Saline 
county,  especially  those  in  the  vicinity  of  Raleigh  and  Galatia,  have  provided 


1915 ] 


McLean  County 


31 


the  University  with  a very  suitable  tract  of  this  type  of  soil  for  a permanent 
experiment  field.  There,  as  an  average  of  duplicate  trials  each  year  for  the  four 
years  1911  to  1914,  the  crop  values  from  four  acres  were  $16.44  from  untreated 
land,  $18.22  where  organic  manures  were  applied  in  proportion  to  the  amount 
of  crops  produced,  and  $33.58  where  6 tons  per  acre  of  limestone  and  the  organic 
manures  were  applied, — the  wheat,  corn,  oats,  and  clover  (or  cowpeas  or  soy- 
beans) grown  in  the  rotation  being  valued  at  the  “lower  prices”  heretofore  men- 
tioned. Owing  to  the  low  supply  of  organic  matter,  phosphorus  produced  almost 
no  benefit,  as  an  average,  during  the  first  two  years ; but  with  increasing  applica- 
tions of  organic  matter,  the  effect  of  phosphorus  is  becoming  more  apparent  in 
subsequent  crops.  Of  course  the  full  benefit  of  a four-year  rotation  cannot  be 
realized  during  the  first  four  years.  The  farm  manure  was  applied  to  one  field 
each  year,  and  the  fourth  field  received  no  manure  until  the  fourth  year.  Like- 
wise, crop  residues  plowed  under  during  the  first  rotation  may  not  be  fully  recov- 
ered in  subsequent  increased  yields  until  the  second  or  third  rotation  period. 

While  limestone  is  the  material  first  needed  for  the  economic  improvement 
of  the  more  acid  soils  of  southern  Illinois,  with  organic  manures  and  phosphorus 
to  follow  in  order,  the  less  acid  soils  of  the  central  part  of  the  state  are  first  in 
need  of  phosphorus,  altho  limestone  and  organic  matter  must  also  be  provided  for 
permanent  and  best  results. 

Table  12  shows  in  detail  thirteen  years’  results  secured  from  the  Antioch 
soil  experiment  field  located  in  Lake  county  on  the  yellow-gray  silt  loam  of  the 
late  Wisconsin  glaciation.  In  acidity  this  type  in  McLean  county  is  intermediate 
between  the  similar  soils  in  Saline  and  Lake  counties,  but  no  experiment  field 
has  been  conducted  on  this  important  soil  type  in  the  early  Wisconsin  glaciation, 
in  which  McLean  county  is  situated. 

The  Antioch  field  was  started  in  order  to  learn  as  quickly  as  possible  what 
effect  would  be  produced  by  the  addition  to  this  type  of  soil,  of  nitrogen,  phos- 
phorus, and  potassium,  singly  and  in  combination.  These  elements  were  all 
added  in  commercial  form  until  1911,  after  which  the  use  of  commercial  nitrogen 
was  discontinued  and  crop  residues  were  substituted  in  its  place.  (See  report  of 
Urbana  field  for  further  explanations,  page  7.)  Only  a small  amount  of  lime 
was  applied  at  the  beginning,  in  harmony  with  the  teaching  which  was  common 
at  that  time;  furthermore,  Plot  101  proved  to  be  abnormal,  so  that  no  conclu- 
sions can  be  drawn  regarding  the  effect  of  lime.  In  order  to  ascertain  the  effect 
produced  by  additions  of  the  different  elements  singly,  Plot  102  must  be  re- 
garded as  the  check  plot.  Three  other  comparisons  are  also  possible  to  deter- 
mine the  effect  of  each  element  under  different  conditions. 

As  an  average  of  40  tests  (4  each  year  for  ten  years),  liberal  applications 
of  commercial  nitrogen  produced  a slight  decrease  in  crop  values;  but  as  an 
average  of  thirteen  years  each  dollar  invested  in  phosphorus  paid  back  $2.54 
(Plot  104),  while  potassium  applied  in  addition  to  phosphorus  (Plot  108)  pro- 
duced no  increase,  the  crops  being  valued  at  the  lower  prices  used  in  the  tabular 
statement.  Thus,  while  the  detailed  data  show  great  variation,  owing  both  to 
some  irregularity  of  soil  and  to  some  very  abnormal  seasons,  with  three  almost 
complete  crop  failures  (1904,  1907,  and  1910),  yet  the  general  summary  strongly 
confirms  the  analytical  data  in  showing  the  need  of  applying  phosphorus  and 
the  profit  from  its  use,  and  the  loss  in  adding  potassium.  In  most  cases  com- 


Soil  Keport  No.  10 


■**  .. 

c3  ^ 
© 'Z* 

|s 

Bushels  or  tons  per  acre 

30.8 

30.0 

40.8 

54.2 

34.0 

41.3 

43.2 

46.0 

41.0 

37.8 

Clover 

1913’ 

O O 
IO  CD 

C) 

1.32 

.72 

C) 

C> 

1.60 

CC 

Oats 

1912 

21.3 

17.5 

24.4 

49.1 

18.8 

46.9 

16.9 

35.9 

31.9 

38.1 

Corn 

1911 

34.4 

24.6 

10.4 

37.4 

20.4 

37.0 

7.0 

42.2 

44.2 

49.0 

Corn 

1910 

CM  O 

^ OO  CD 

rH  CD' 

© CD  CM 
CD  rH  CO* 

o o 

CO*  TtH 

Wheat 

1909 

1 12.2 
11.7 

© CO  iq 
CO  go  CO 

00  © CM 
CO  rH  CD 
CO  CM  CM 

30.5 

34.5 

Oats 

1908 

65.6 

61.6 

60.3 

70.9 

62.5 

49.1 

52.6 

59.4 

51.9 

55.9 

Corn 

1907 

12.4 

9.5 

6.4 

13.4 

12.9 

20.9 

11.1 

18.3 

31.4 

28.8 

Corn 

1906 

1 35.9 

31.5 

CO  ^ 05 
rji 

CO  ID  CO 

CO  © H 
05  05*  05* 

IO  CO  io 

65.9 
I 66.3 

Wheat 

1905 

18.5 

10.3 

17.8 

35.8 
21.7 

15.2 

11.8 

28.7 

18.0 

16.3 

Oats 

1904 

17.8  1 

12.8 

loo  iq  o. 

©d  CM*  05 
1 M 

05  CO 
IO*  © 05 

31.9 

37.2 

Corn 

1903 

CD  05 

c 6 oo 

CO  CO 

40.8 

53.6 

50.2 

62.7 

54.9 

66.0 

69.1 

71.8 

Corn 

1902 

TtH  LO 

46.3 

50.1 

48.2 

OHS 
CD  <M*  O* 
IO  IO  CD 

61.2 

59.7 

Yellow-gray  silt  loam,  undulating 
timberland;  late  Wisconsin 
glaciation 

Soil  treatment 
applied1 

© © 
§ a 

[me,  nitrogen • 

ime,  phosphorus  

ime,  potassium  

ime,  nitrogen,  phosphorus  

ime,  nitrogen,  potassium 

ime,  phosphorus,  potassium 

Lime,  nitrogen,  phosphorus,  potas- 

sium  

Nitrogen,  phosphorus,  potassium .... 

£ h 

Plot 

!-»  (M 

lss 

CO  IO 

© o © 

CD  tv  00 
© © © 

109 

110 

cq  oo  cm  ^ CD 

* (m‘  r 

Hi  CM 


) CO  05  oo  CM  CC 


'IO  lO  ID 


CO  05  ^ 05  IO 
CO  IO  CO  rH  rH 
CM  CM 


1C  LO  rJH  CO  CO  GO 
t>-‘  IO*  tH  © cm  CM 
CM  H CM  | 


S © w 

O.  bo  ? 


a 5 

§D  &© 


[May, 


’Crop  residues  in  place  of  commercial  nitrogen  after  1911. 

’Figures  in  parentheses  indicate  bushels  of  seed;  the  others,  tons  of  hay. 
aNo  seed  produced:  clover  plowed  under  on  these  plots. 


1915] 


McLean  County 


33 


Table  13. — Value  of  Crops  per  Acre  in  Thirteen  Years,  Antioch  Field 


Plot 

Soil  treatment  applied 

Total  value  of 
thirteen  crops 

Lower 

prices1 

Higher 

prices2 

101 

None  

$135.12 

$193.03 

102 

119.74 

171.06 

103 

Lime,  nitrogen 

124.70 

178.15 

104 

Lime,  phosphorus  

202.20 

288.85 

105 

Lime,  potassium 

138.88 

198.40 

106 

Lime,  nitrogen,  phosphorus 

T79.41 

256.31 

107 

Lime,  nitrogen,  potassium 

133.54 

190.77 

108 

Nitrogen,  phosphorus,  potassium 

201.35 

287.65 

109 

Lime,  nitrogen,  phosphorus,  potassium 

191.22 

273.18 

110 

Nitrogen,  phosphorus,  potassium 

181.18 

258.83 

Value  of  Increase  per  Acre  in  Thirteen  Years 


For  nitrogen 

1 $ 4.96 

$ 7.09 

For  phosphorus  

82.46 

117.79 

For  nitrogen  and  phosphorus  over  phosphorus 

-22.79 

-32.54 

For  phosphorus  and  nitrogen  over  nitrogen 

54.71 

78.16 

For  potassium,  nitrogen,  and  phosphorus  over  nitrogen  and  phosphorus . . . 

11.81 

16.87 

'Wheat  at  70  cents  a bushel,  corn  at  35  cents,  oats  at  28  cents,  hay  at  $7  a ton. 
“Wheat  at  $1  a bushel,  corn  at  50  cents,  oats  at  40  cents,  hay  at  $10  a ton. 


mercial  nitrogen  damaged  the  small  grains  by  causing  the  crop  to  lodge ; but  in 
those  years  when  a corn  yield  of  40  bushels  or  more  was  secured  by  the  appli- 
cation of  phosphorus  either  alone  or  with  potassium,  then  the  addition  of  nitro- 
gen produced  an  increase. 

From  a comparison  of  the  results  from  the  Urbana,  Sibley,  and  Blooming- 
ton fields,  we  must  conclude  that  better  yields  are  to  be  secured  by  providing 
nitrogen  by  means  of  farm  manure  or  legume  crops  grown  in  the  rotation  than 
by  the  use  of  commercial  nitrogen,  which  is  evidently  too  readily  available,  caus- 
ing too  rapid  growth  and  consequent  weakness  of  straw ; and  of  course  the  at- 
mosphere is  the  most  economic  source  of  nitrogen  where  that  element  is  needed 
for  soil  improvement  in  general  farming.  ( See  Appendix  for  detailed  discussion 
of  “Permanent  Soil  Improvement.”) 

Yellow  Silt  Loam  (1135  or  935) 

Yellow  silt  loam  covers  27.43  square  miles  (17,555  acres)  and  constitutes 
2.36  percent  of  the  entire  area  of  the  county.  It  occurs  as  the  hilly  and  badly 
eroded  land  on  the  inner  timber  belts  adjacent  to  the  streams,  usually  only  in 
narrow,  irregular  strips  with  arms  extending  up  the  small  valleys.  In  topog- 
raphy it  is  very  rolling,  and  in  most  places  so  badly  broken  that  it  should  not  be 
cultivated  because  of  the  danger  of  injury  from  washing. 

The  surface  soil,  0 to  6%  inches,  is  a yellow  or  grayish  yellow,  pulverulent 
silt  loam.  It  varies  greatly  in  color  and  texture,  owing  to  recent  washing.  In 
places  the  natural  subsoil  may  be  exposed.  This  exposure  gives  it  a decidedly 
yellow  color.  The  soil  freshly  plowed  appears  yellow  or  brownish  yellow,  but  when 
it  becomes  dry  after  a rain,  it  is  of  a grayish  color.  In  some  places  the  surface  soil 
is  formed  from  glacial  drift,  but  this  is  only  on  very  limited  areas  and  on  the 
steepest  slopes.  The  organic-matter  content  is  the  lowest  of  any  type  in  the 
county,  being  only  1.5  percent,  or  15  tons  per  acre.  It  varies,  however,  from  1.2 
to  1.8  percent. 


34 


Soil  Repoet  No.  10 


[May, 


The  subsurface  varies  from  a yellow  silt  loam  to  a yellow  clayey  silt  loam, 
and  on  the  steepest  slopes  may  consist  of  weathered  glacial  drift.  The  thickness 
of  the  stratum  varies  from  5 to  12  inches,  depending  on  the  amount  of  recent 
erosion.  The  organic-matter  content  amounts  to  only  12  tons  per  acre. 

The  subsoil  consists  normally  of  a yellow  clayey  silt,  but  in  some  areas  may 
be  composed  entirely  of  glacial  drift. 

The  first  and  most  important  thing  in  the  management  of  this  type  is  to  pre- 
vent general  surface  washing  and  gullying.  If  the  land  is  cropped  at  all,  a rota- 
tion should  be  practiced  that  will  require  a cultivated  crop  as  little  as  possible, 
and  allow  pasture  and  meadow  most  of  the  time.  If  tilled,  the  land  should  be 
plowed  deeply  and  contours  should  be  followed  as  nearly  as  possible  in  plowing, 
planting,  and  cultivating.  Furrows  should  not  be  made  up  and  down  the  slopes. 
Every  means  should  be  employed  to  maintain  and  increase  the  organic-matter 
content.  This  will  help  hold  the  soil  and  keep  it  in  good  physical  condition  so 
that  it  will  absorb  a large  amount  of  water  and  thus  diminish  the  run-off.  (See 
Circular  119,  “Washing  of  Soils  and  Methods  of  Prevention.”) 

Additional  treatment  recommended  for  this  yellow  silt  loam  is  the  liberal 
use  of  limestone  wherever  cropping  is  practiced.  This  type  is  quite  acid  and 
very  deficient  in  nitrogen;  and  the  limestone,  by  correcting  the  acidity  of  the 
soil,  is  especially  beneficial  to  the  clover  grown  to  increase  the  supply  of  nitro- 
gen. Where  this  soil  has  been  long  cultivated  and  thus  exposed  to  surface  wash- 
ing, it  is  particularly  deficient  in  nitrogen ; indeed,  on  such  lands  the  low  supply 
of  nitrogen  is  the  factor  that  first  limits  the  growth  of  grain  crops.  This  fact 
is  very  strikingly  illustrated  by  the  results  from  two  pot-culture  experiments  re- 
ported in  Tables  14  and  15,  and  shown  photographically  in  Plates  7 and  8. 

In  one  experiment,  a large  quantity  of  the  typical  worn  hill  soil  was  col- 
lected from  two  different  places.1  Each  lot  of  soil  was  thoroly  mixed  and  put 
in  ten  four- gallon  jars.  Ground  limestone  was  added  to  all  the  jars  except  the 
first  and  last  in  each  set,  those  two  being  retained  as  control  or  check  pots.  The 
elements  nitrogen,  phosphorus,  and  potassium  were  added  singly  and  in  com- 
bination, as  shown  in  Table  14. 

As  an  average,  the  nitrogen  applied  produced  a yield  about  eight  times  as 
large  as  that  secured  without  the  addition  of  nitrogen.  While  some  variations 
in  yield  are  to  be  expected,  because  of  differences  in  the  individuality  of  seed  or 
other  uncontrolled  causes,  yet  there  is  no  doubting  the  plain  lesson  taught  by 
these  actual  trials  with  growing  plants. 

The  question  arises  next,  Where  is  the  farmer  to  secure  this  much-needed 
nitrogen  ? To  purchase  it  in  commercial  fertilizers  would  cost  too  much ; indeed, 
under  average  conditions  the  cost  of  the  nitrogen  in  such  fertilizers  is  greater 
than  the  value  of  the  increase  in  crop  yields. 

But  there  is  no  need  whatever  to  purchase  nitrogen,  for  the  air  contains  an 
inexhaustible  supply  of  it,  which,  under  suitable  conditions,  the  farmer  can  draw 
upon,  not  only  without  cost,  but  with  profit  in  the  getting.  Clover,  alfalfa,  cow- 
peas,  and  soybeans  are  not  only  worth  raising  for  their  own  sake,  but  they  have 
the  power  to  secure  nitrogen  from  the  atmosphere  if  the  soil  contains  limestone- 
and  the  proper  nitrogen-fixing  bacteria. 

1Soil  for  wheat  pots  from  loess-covered  unglaciated  area,  and  that  for  oat  pots  from/ 
upper  Illinois  glaciation. 


1915] 


McLean  County  * 


35 


To  secure  further  information  along  this  line,  another  experiment  with  pot 
cultures  was  conducted  for  several  years  with  the  same  type  of  worn  hill  soil  as 
that  used  for  wheat  in  the  former  experiment.  The  results  are  reported  in 
Table  15. 

To  three  pots  (Nos.  3,  6,  and  9)  nitrogen  was  applied  in  commercial  form, 
at  an  expense  amounting  to  more  than  the  total  value  of  the  crops  produced.  In 
three  other  pots  (Nos.  2,  11,  and  12)  a crop  of  cowpeas  was  grown  during  the 
late  summer  and  fall  and  turned  under  before  the  wheat  or  oats  were  planted. 
Pots  1 and  8 served  for  important  comparisons.  After  the  second  cover  crop  of 
cowpeas  had  been  turned  under,  the  yield  from  Pot  2 exceeded  that  from  Pot  3 ; 
and  in  the  subsequent  years  the  legume  green  manures  produced,  as  an  average, 
rather  better  results  than  the  commercial  nitrogen.  This  experiment  confirms 
that  reported  in  Table  14,  in  showing  the  very  great  need  of  nitrogen  for  the 
improvement  of  this  type  of  soil,  and  it  also  shows  that  nitrogen  need  not  be 
purchased  but  that  it  can  be  obtained  from  the  air  by  growing  legume  crops  and 
plowing  them  under  as  green  manure.  Of  course  the  soil  can  be  very  markedly 
improved  by  feeding  the  legume  crops  to  live  stock  and  returning  the  resulting 


Plate  7. — Wheat  in  Pot-Culture  Experiment  with  Yellow  Silt  Loam  of  Worn  Hill  Land 
(See  Table  14) 


Table  14. — Crop  Yields  in  Pot-Culture  Experiment  with  Yellow  Silt  Loam  of  Worn 

Hill  Land 

(Grams  per  pot) 


Pot 

No. 

Soil  treatment  applied 

Wheat 

Oats 

1 

None 

3 

5 

2 

Limestone 

4 

4 

3~ 

Limestone,  nitrogen 

26 

45 

4 

Limestone,  phosphorus 

3 

6 

5 

Limestone,  potassium 

3 

5 

6 

Limestone,  nitrogen,  phosphorus 

34 

38 

7 

Limestone,  nitrogen,  potassium 

33 

46 

8 

Limestone,  phosphorus,  potassium 

2 

5 

9 

Limestone,  nitrogen,  phosphorus,  potassium 

34 

38 

10 

3 

5 

Average  yield  with  nitrogen 

32 

42 

Average  yield  without  nitrogen 

3 

5 

Average  train  for  nitrocron 

29 

37 

36 


Soil  Report  No.  10 


[May, 


farm  manure  to  the  land,  if  legumes  are  grown  frequently  enough  and  if  the  farm 
manure  produced  is  sufficiently  abundant  and  is  saved  and  applied  with  care. 

As  a rule,  it  is  not  advisable  to  try  to  enrich  this  type  of  soil  in  phosphorus, 
for  with  the  erosion  that  is  sure  to  occur  to  some  extent  the  phosphorus  supply 
will  be  renewed  from  the  subsoil. 

Probably  the  best  legumes  for  this  type  of  soil  are  sweet  clover  and  alfalfa. 
On  soil  deficient  in  organic  matter  sweet  clover  grows  better  than  almost  any 
other  legume,  and  the  fact  that  it  is  a very  deep-rooting  plant  makes  it  of  value 
in  increasing  organic  matter  and  preventing  washing.  Worthless  slopes  that 
have  been  ruined  by  washing  may  be  made  profitable  as  pasture  by  growing  sweet 
clover.  The  blue  grass  of  pastures  may  well  be  supplemented  by  sweet  clover 
and  alfalfa,  and  a larger  growth  obtained,  because  the  legumes  provide  the  neces- 
sary nitrogen  for  the  blue  grass. 

To  get  alfalfa  well  started  requires  the  liberal  use  of  limestone,  thoro  inocu- 
lation with  nitrogen-fixing  bacteria,  and  a moderate  application  of  farm  manure. 
If  manure  is  not  available,  it  is  well  to  apply  abodt  500  pounds  per  acre  of  acid 
phosphate,  or  steamed  bone  meal,  mix  it  with  the  soil,  by  disking  if  possible,  and 
then  plow  it  under.  The  limestone  (about  5 tons)  should  be  applied  after  plow- 
ing and  should  be  mixed  with  the  surface  soil  in  the  preparation  of  the  seed  bed. 
The  special  purpose  of  this  treatment  is  to  give  the  alfalfa  a quick  start  in  order 
that  it  may  grow  rapidly  and  thus  protect  the  soil  from  washing. 


Plate  8. — Wheat  in  Pot-Culture  Experiment  with  Yellow  Silt  Loam  op  Worn  Hill  Land 
(See  Table  15) 

Table  15. — Crop  Yields  in  Pot-Culture  Experiment  with  Yellow  Silt  Loam  of  Worn  Hill 
Land  and  Nitrogen-Fixing  Green  Manure  Crops 


(Grains  per  pot) 


Pot 

No. 

Soil  treatment 

1903 

Wheat 

1904 

Wheat 

1905 

Wheat 

1906  | 
Wheat 

1907 

Oats 

1 

None  

5 

4 

4 

4 

6 

2 

Limestone,  legume  

10 

17 

26 

19 

37 

11 

Limestone,  legume,  phosphorus  

14 

19 

20 

18 

27 

12 

Limestone,  legume,  phosphorus,  potassium. . 

16 

20 

21 

19 

30 

3 

Limestone,  nitrogen  

17 

14 

15 

9 

28 

6 

Limestone,  nitrogen,  phosphorus  

26 

20 

18 

18 

30 

9 

Limestone,  nitrogen,  phosphorus,  potassium 

31 

34 

21 

20 

26 

8 

Limestone,  phosphorus,  potassium  

3 

3 

5 

3 

7 

1915 ] 


McLean  County 


37 


(c)  Terrace  Soils 

Terrace  soils  were  formed  on  terraces  or  old  fills  in  valleys.  The  terraces 
owe  their  formation  generally  to  the  deposition  of  material  from  an  overloaded 
and  flooded  stream  during  the  melting  of  the  glaciers.  The  material  varied  from 
fine  to  coarse.  These  valleys  were  sometimes  filled  almost  to  the  height  of  the 
upland.  Later  the  streams  cut  down  thru  these  fills  and  developed  new  bottom 
lands,  or  flood  plains,  at  a lower  level,  leaving  part  of  the  old  fill  as  a terrace.  The 
lowest  and  most  recently  formed  bottom  land  is  called  first  bottom.  The  higher 
land  no  longer  flooded  (or  very  rarely,  at  most)  is  generally  designated  as  second 
bottom.  Finer  material  later  deposited  on  this  sand  and  gravel  of  the  fill  now 
constitutes  the  soil.  The  terraces  occur  along  the  Mackinaw  and  Sangamon  rivers. 

Brown  Silt  Loam  over  Gravel  (1527) 

Brown  silt  loam  over  gravel  occurs  along  the  Sangamon  river  in  very  limi- 
ted areas.  The  total  area  is  only  166  acres. 

The  surface  soil,  0 to  6%  inches,  is  a brown  to  a dark  brown  silt  loam,  con- 
taining some  sand  and  5.7  percent  of  organic  matter,  or  57  tons  per  acre.  The 
topography  is  slightly  undulating. 

The  subsurface  soil  varies  from  a brown  to  a yellowish  brown  or  yellowish 
drab  silt  loam,  and  the  lower  part  of  the  stratum  at  a depth  of  16  to  18  inches 
contains  fragments  of  sand  and  gravel. 

The  subsoil  is  a yellowish  or  drab-colored  silt  or  clayey  silt,  which  becomes 
quite  gravelly  at  35  to  48  inches  and  passes  into  rather  a pure  gravel. 

This  type,  as  a rule,  is  well  drained,  because  of  the  pervious  character  of  the 
subsoil.  The  treatment  should  be  the  same  as  for  brown  silt  loam,  except  that  the 
addition  of  phosphorus  is  not  likely  to  be  profitable,  because  of  the  deep  feeding 
range  afforded  plant  roots.  < 

Brown  Silt  Loam  on  Gravel  (1526.2) 

Brown  silt  loam  on  gravel  covers  an  area  of  1.77  square  miles  (1,132  acres) , 
or  only  .15  percent  of  the  total  area  of  the  county.  It  differs  from  the  brown  silt 
loam  over  gravel  only  in  the  fact  that  gravel  is  within  30  inches  of  the  surface. 
Because  of  the  nearness  of  the  gravel  the  type  is  more  susceptible  to  drouth  than 
if  this  stratum  were  deeper. 

The  treatment  for  this  type  should  be  practically  the  same  as  for  the  preced- 
ing. There  is,  however,  a greater  necessity  for  increasing  the  organic  matter, 
because  the  soil  contains  less  of  that  constituent. 

Yellow-Gray  Silt  Loam  on  Gravel  (1534.2) 

Yellow-gray  silt  loam  on  gravel  is  found  along  both  the  Mackinaw  and  San- 
gamon rivers.  It  represents  the  terrace  soil  that  has  been  covered  by  a growth  of 
trees  and  is  consequently  low  in  organic  matter.  The  total  area  is  621  acres. 

The  surface  soil,  0 to  6%  inches,  is  a yellow  or  yellowish  gray  silt  loam  with 
an  organic-matter  content  of  3.1  percent,  or  31  tons  per  acre. 

The  subsurface  is  a yellow  silt  loam  containing  a perceptible  amount  of  sand. 

The  subsoil  is  a yellow  silt  or  clayey  silt,  passing  into  the  gravel  at  a depth 
of  12  to  30  inches.  Local  borings  are  obtained  where  the  gravel  layer  may  be 
slightly  below  30  inches. 


38 


Soil  Report  No.  10 


[May, 


This  soil  needs  nitrogen  and  organic  matter  as  the  most  essential  things  in 
its  improvement. 

(d)  Swamp  and  Bottom-Land  Soils 
Deep  Peat  (1401) 

A few  small  areas  of  deep  peat,  aggregating  83  acres,  are  mapped  in  this 
county.  They  occur  in  low,  poorly  drained  places  in  bottom  land  or  swamps. 

The  surface  soil,  0 to  6%  inches,  is  black,  generally  well  decomposed,  and 
contains  about  55  percent  of  organic  matter.  The  subsurface  is  very  similar  to 
the  surface,  but  the  organic-matter  content  is  not  so  high,  being  about  50  percent. 
The  subsoil  is  quite  variable ; in  some  places  it  passes  into  a drab  silty  clay  and  in 
others  it  is  peaty  to  a depth  of  40  inches.  It  frequently  contains  shells  mingling 
with  the  organic  matter. 

Drainage  is  of  course  the  first  essential  for  this  type.  If  it  does  not  produce 
well  when  drained,  trials  should  be  made  with  potassium.  (See  Bulletin  157.) 

Deep  Brown  Silt  Loam  ( Bottom  Land)  (1426) 

Deep  brown  silt  loam  occurs  along  the  streams,  chiefly  in  the  southwestern 
part  of  the  county.  It  aggregates  23.88  square  miles,  or  2 percent  of  the  county. 

The  surface  soil,  0 to  6%  inches,  is  a brown  silt  loam  containing  from  5 to  8 
percent  of  organic  matter.  It  varies  somewhat  in  physical  composition  from  a 
heavy  phase  to  one  containing  sand  in  sufficient  amounts  to  be  called  a sandy 
loam.  This  latter,  however,  does  not  occur  in  areas  large  enough  to  be  mapped. 

The  subsurface  soil  is  similar  to  the  surface  except  that  the  organic-matter 
content  is  slightly  lower,  varying  from  4 to  7 percent,  and  consequently  the  soil 
is  a little  lighter  in  color.  The  subsoil  is  not  so  dark  as  the  surface  and  contains 
local  areas  of  coarse  material. 

Where  proper  drainage  is  secured,  this  type  is  very  productive.  As  a rule, 
where  it  is  subject  to  frequent  overflow  nothing  else  is  needed  except  good  farm- 
ing. Even  the  systematic  rotation  of  crops  is  not  so  important  where  the  land  is 
subject  to  occasional  overflow;  but  where  it  lies  high  or  is  protected  from  over- 
flow by  dikes,  a rotation  including  legume  crops  should  be  practiced,  and  ulti- 
mately provision  should  be  made  for  the  enrichment  of  such  protected  land  in 
both  phosphorus  and  organic  matter,  and,  if  acid,  in  limestone. 

Mixed  Loam  ( Bottom  Land)  (1454) 

Mixed  loam  occurs  chiefly  north  of  the  Bloomington  moraine.  It  aggregates 
18  square  miles,  or  1.5  percent  of  the  county.  It  varies  quite  widely  in  its  physi- 
cal composition,  including  sand,  sandy  loam,  silt  loam,  and  possibly  some  clay 
loam.  Its  character  changes  more  or  less  with  each  flood ; hence  it  is  impracti- 
cable to  attempt  to  separate  it  into  distinct  types.  The  amount  of  organic  matter 
in  the  surface  soil  is  about  5.5  percent,  which  is  equivalent  to  55  tons  per  acre. 

The  subsurface  is  a dark  soil,  varying  in  physical  composition  from  a sandy 
loam  to  a clay  loam.  The  organic-matter  content  is  about  4.6  percent. 

The  subsoil  is  slightly  lighter  in  color  than  the  subsurface,  with  a variable 
composition  similar  to  that  of  the  other  strata. 

This  type  is  fertile,  and  no  treatment  is  suggested  beyond  that  mentioned  for 
the  preceding  type,  deep  brown  silt  loam. 


1915] 


McLean  County 


39 


APPENDIX 

A study  of  the  soil  map  and  the  tabular  statements  concerning  crop  require- 
ments, the  plant-food  content  of  the  different  soil  types,  and  the  actual  results 
secured  from  definite  field  trials  with  different  methods  or  systems  of  soil  im- 
provement, and  a careful  study  of  the  discussion  of  general  principles  and  of 
the  descriptions  of  individual  soil  types,  will  furnish  the  most  necessary  and  use- 
ful information  for  the  practical  improvement  and  permanent  preservation  of 
the  productive  power  of  every  kind  of  soil  on  every  farm  in  the  county. 

More  complete  information  concerning  the  most  extensive  and  important  soil 
types  in  the  great  soil  areas  in  all  parts  of  Illinois  is  contained  in  Bulletin  123, 
“The  Fertility  in  Illinois  Soils,”  which  contains  a colored  general  soil-survey 
map  of  the  entire  state. 

Other  publications  of  general  interest  are : 

Bulletin  No.  76,  “Alfalfa  on  Illinois  Soils” 

Bulletin  No.  94,  ‘ ‘ Nitrogen  Bacteria  and  Legumes  ’ ’ 

Bulletin  No.  115,  “Soil  Improvement  for  the  Worn  Hill  Lands  of  Illinois” 

Bulletin  No.  125,  “Thirty  Years  of  Crop  Botation  on  the  Common  Prairie  Lands  of 
Illinois” 

Circular  No.  82,  ‘ ‘ Physical  Improvement  of  Soils  ’ ’ 

Circular  No.  110,  “Ground  Limestone  for  Acid  Soils” 

Circular  No.  127,  “Shall  We  Use  Natural  Rock  Phosphate  or  Manufactured  Acid  Phos- 
phate for  the  Permanent  Improvement  of  Illinois  Soils?” 

Circular  No.  129,  “The  Use  of  Commercial  Fertilizers” 

Circular  No.  149,  “Results  of  Scientific  Soil  Treatment”  and  “Methods  and  Results  of 
Ten  Years’  Soil  Investigation  in  Illinois” 

Circular  No.  165,  “Shall  We  Use  ‘Complete’  Commercial  Fertilizers  in  the  Corn  Belt?” 

Circular  No.  167,  “The  Illinois  System  of  Permanent  Fertility” 

Note. — Information  as  to  where  to  obtain  limestone,  phosphate,  bone  meal,  and  potas- 
sium salts,  methods  of  application,  etc.,  will  also  be  found  in  Circulars  110  and  165. 

Soil  Survey  Methods 

The  detail  soil  survey  of  a county  consists  essentially  of  ascertaining,  and 
indicating  on  a map,  the  location  and  extent  of  the  different  soil  types;  and, 
since  the  value  of  the  survey  depends  upon  its  accuracy,  every  reasonable  means 
is  employed  to  make  it  trustworthy.  To  accomplish  this  object  three  things  are 
essential : first,  careful,  well-trained  men  to  do  the  work ; second,  an  accurate 
base  map  upon  which  to  show  the  results  of  the  work;  and,  third,  the  means 
necessary  to  enable  the  men  to  place  the  soil-type  boundaries,  streams,  etc., 
accurately  upon  the  map. 

The  men  selected  for  the  work  must  be  able  to  keep  their  location  exactly 
and  to  recognize  the  different  soil  types,  with  their  principal  variations  and  lim- 
its, and  they  must  show  these  upon  the  maps  correctly.  A definite  system  is 
employed  in  checking  up  this  work.  As  an  illustration,  one  soil  expert  will  sur- 
vey and  map  a strip  80  rods  or  160  rods  wide  and  any  convenient  length,  while 
his  associate  will  work  independently  on  another  strip  adjoining  this  area,  and, 
if  the  work  is  correctly  done,  the  soil  type  boundaries  must  match  up  on  the 
line  between  the  two  strips. 

An  accurate  base  map  for  field  use  is  absolutely  necessary  for  soil  mapping. 
The  base  maps  are  made  on  a scale  of  one  inch  to  the  mile.  The  official  data 
of  the  original  or  subsequent  land  survey  are  used  as  a basis  in  the  construc- 
tion of  these  maps,  while  the  most  trustworthy  county  map  available  is  used  in 


40 


Soil  Report  No.  10 


[May, 


locating  temporarily  the  streams,  roads,  and  railroads.  Since  the  best  of  these 
published  maps  have  some  inaccuracies,  the  location  of  every  road,  stream,  and 
railroad  must  be  verified  by  the  soil  surveyors,  and  corrected  if  wrongly  located. 
In  order  to  make  these  verifications  and  corrections,  each  survey  party  is  pro- 
vided with  an  odometer  for  measuring  distances,  and  a plane  table  for  deter- 
mining directions  of  angling  roads,  railroads,  etc. 

Each  surveyor  is  provided  with  a base  map  of  the  proper  scale,  which  is 
carried  with  him  in  the  field ; and  the  soil-type  boundaries,  ditches,  streams,  and 
necessary  corrections  are  placed  in  their  proper  locations  upon  the  map  while 
the  mapper  is  on  the  area.  Each  section,  or  square  mile,  is  divided  into  40-acre 
plots  on  the  map,  and  the  surveyor  must  inspect  every  ten  acres  and  determine 
the  type  or  types  of  soil  composing  it.  The  different  types  are  indicated  on  the 
map  by  different  colors,  pencils  for  this  purpose  being  carried  in  the  field. 

A small  auger  40  inches  long  forms  for  each  man  an  invaluable  tool  with 
which  he  can  quickly  secure  samples  of  the  different  strata  for  inspection.  An 
extension  for  making  the  auger  80  inches  long  is  carried  by  each  party,  so  that 
any  peculiarity  of  the  deeper  subsoil  layers  may  be  studied.  Each  man  carries 
a compass  to  aid  in  keeping  directions.  Distances  along  roads  are  measured  by 
an  odometer  attached  to  the  axle  of  the  vehicle,  while  distances  in  the  field  off 
the  roads  are  determined  by  pacing,  an  art  in  which  the  men  become  expert  by 
practice.  The  soil  boundaries  can  thus  be  located  with  as  high  a degree  of  ac- 
curacy as  can  be  indicated  by  pencil  on  the  scale  of  one  inch  to  the  mile. 


The  unit  in  the  soil  survey  is  the  soil  type,  and  each  type  possesses  more  or 
less  definite  characteristics.  The  line  of  separation  between  adjoining  types  is 
usually  distinct,  but  sometimes  one  type  grades  into  another  so  gradually  that 
it  is  very  difficult  to  draw  the  line  between  them.  In  such  exceptional  cases, 
some  slight  variation  in  the  location  of  soil-type  boundaries  is  unavoidable. 

Several  factors  must  be  taken  into  account  in  establishing  soil  types.  These 
are  (1)  the  geological  origin  of  the  soil,  whether  residual,  glacial,  loessial,  al- 
luvial, colluvial,  or  cumulose;  (2)  the  topography,  or  lay  of  the  land;  (3)  the 
native  vegetation,  as  forest  or  prairie  grasses;  (4)  the  structure,  or  the  depth 
and  character  of  the  surface,  subsurface,  and  subsoil;  (5)  the  physical,  or  me- 
chanical, composition  of  the  different  strata  composing  the  soil,  as  the  percent- 
ages of  gravel,  sand,  silt,  clay,  and  organic  matter  which  they  contain;  (6)  the 
texture,  or  porosity,  granulation,  friability,  plasticity,  etc.;  (7)  the  color  of  the 
strata;  (8)  the  natural  drainage;  (9)  the  agricultural  value,  based  upon  its 
natural  productiveness;  (10)  the  ultimate  chemical  co  ^position  and  reaction. 

The  common  soil  constituents  are  indicated  in  the  following  outline : 


Soil  Characteristics 


Organic 

matter 


I 


Comprising  undeeomposed  and  partially  decayed 
vegetable  or  organic  material 


Soil 

constituents 


Inorganic 

matter 


[Clay. 

Silt. 


001  mm.  to  .03  mm. 
. .03  mm.  to  1.  mm. 
. . . 1.  mm.  to  32  mm. 
. . .32.  mm.  and  over 


,001  mm.1  and  less 


Further  discussion  of  these  constituents  is  given  in  Circular  82. 


*25  millimeters  equal  1 inch. 


1915] 


McLean  County 


41 


Groups  op  Soil  Types 

The  following  gives  the  different  general  groups  of  soils: 

Peats — Consisting  of  35  percent  or  more  of  organic  matter,  sometimes  mixed 
with  more  or  less  sand  or  silt. 

Peaty  loams — 15  to  35  percent  of  organic  matter  mixed  with  much  sand. 
Some  silt  and  a little  clay  may  be  present. 

Mucks — 15  to  35  percent  of  partly  decomposed  organic  matter  mixed  with 
much  clay  and  silt. 

Clays — Soils  with  more  than  25  percent  of  clay,  usually  mixed  with  much 
silt. 

Clay  loams — Soils  with  from  15  to  25  percent  of  clay,  usually  mixed  with 
much  silt  and  some  sand. 

Silt  loams — Soils  with  more  than  50  percent  of  silt  and  less  than  15  percent 
of  clay,  mixed  with  some  sand. 

Loams — Soils  with  from  30  to  50  percent  of  sand  mixed  with  much  silt  and 
a little  clay. 

Sandy  loams — Soils  with  from  50  to  75  percent  of  sand. 

Fine  sandy  loams — Soils  with  from  50  to  75  percent  of  fine  sand  mixed  with 
much  silt  and  little  clay. 

Sands — Soils  with  more  than  75  percent  of  sand. 

Gravelly  loams — Soils  with  25  to  50  percent  of  gravel  with  much  sand  and 
some  silt. 

Gravels — Soils  with  more  than  50  percent  of  gravel  and  much  sand. 

Stony  loams — Soils  containing  a considerable  number  of  stones  over  one  inch 
in  diameter. 

Kock  outcrop — Usually  ledges  of  rock  having  no  direct  agricultural  value. 

More  or  less  organic  matter  is  found  in  all  the  above  groups. 

Supply  and  Liberation  op  Plant  Food 

The  productive  capacity  of  land  in  humid  sections  depends  almost  wholly 
upon  the  power  of  the  soil  to  feed  the  crop ; and  this,  in  turn,  depends  both 
upon  the  stock  of  plant  food  contained  in  the  soil  and  upon  the  rate  at  which 
it  is  liberated,  or  rendered  soluble  and  available  for  use  in  plant  growth. 
Protection  from  weeds,  insects,  and  fungous  diseases,  tho  exceedingly  important, 
is  not  a positive  but  a negative  factor  in  crop  production. 

The  chemical  analysis  of  the  soil  gives  the  invoice  of  fertility  actually  pres- 
ent in  the  soil  strata  sampled  and  analyzed,  but  the  rate  of  liberation  is  gov- 
erned by  many  factors,  some  of  which  may  be  controlled  by  the  farmer,  while 
others  are  largely  beyond  his  control.  Chief  among  the  important  controllable 
factors  which  influence  the  liberation  of  plant  food  are  limestone  and  decaying 
organic  matter,  which  may  be  added  to  the  soil  by  direct  application  of  ground 
limestone  and  farm  manure.  Organic  matter  may  be  supplied  also  by  green- 
manure  crops  and  crop  residues,  such  as  clover,  cowpeas,  straw,  and  corn  stalks. 
The  rate  of  decay  of  organic  matter  depends  largely  upon  its  age  and  origin, 
and  it  may  be  hastened  by  tillage.  The  chemical  analysis  shows  correctly  the 


42 


Soil  Report  No.  10 


\May, 


total  organic  carbon,  which  represents,  as  a rule,  but  little  more  than  half  the 
organic  matter ; so  that  20,000  pounds  of  organic  carbon  in  the  plowed  soil  of 
an  acre  correspond  to  nearly  20  tons  of  organic  matter.  But  this  organic  mat- 
ter consists  largely  of  the  old  organic  residues  that  have  accumulated  during  the 
past  centuries  because  they  were  resistant  to  decay,  and  2 tons  of  clover  or 
cuwpeas  plowed  under  may  have  greater  power  to  liberate  plant  food  than  the 
20  tons  of  old,  inactive  organic  matter.  The  recent  history  of  the  individual 
farm  or  field  must  be  depended  upon  for  information  concerning  recent  addi- 
tions of  active  organic  matter,  whether  in  applications  of  farm  manure,  in 
legume  crops,  or  in  grass-root  sods  of  old  pastures. 

Probably  no  agricultural  fact  is  more  generally  known  by  farmers  and  land- 
owners  than  that  soils  differ  in  productive  power.  Even  tho  plowed  alike  and 
at  the  same  time,  prepared  the  same  way,  planted  the  same  day  with  the  same 
kind  of  seed,  and  cultivated  alike,  watered  by  the  same  rains  and  warmed  by 
the  same  sun,  nevertheless  the  best  acre  may  produce  twice  as  large  a crop  as 
the  poorest  acre  on  the  same  farm,  if  not,  indeed,  in  the  same  field ; and  the 
fact  should  be  repeated  and  emphasized  that  with  the  normal  rainfall  of  Illi- 
nois the  productive  power  of  the  land  depends  primarily  upon  the  stock  of  plant 
food  contained  in  the  soil  and  upon  the  rate  at  which  it  is  liberated,  just  as 
the  success  of  the  merchant  depends  primarily  upon  his  stock  of  goods  and  the 
rapidity  of  sales.  In  both  cases  the  stock  of  any  commodity  must  be  increased 
or  renewed  whenever  the  supply  of  such  commodity  becomes  so  depleted  as  to 
limit  the  success  of  the  business,  whether  on  the  farm  or  in  the  store. 

As  the  organic  matter  decays,  certain  decomposition  products  are  formed, 
including  much  carbonic  acid,  some  nitric  acid,  and  various  organic  acids,  and 
these  have  power  to  act  upon  the  soil  and  dissolve  the  essential  mineral  plant 
foods,  thus  furnishing  soluble  phosphates,  nitrates,  and  other  salts  of  potassium, 
magnesium,  calcium,  etc.,  for  the  use  of  the  growing  crop. 

As  already  explained,  fresh  organic  matter  decomposes  much  more  rapidly 
than  old  humus,  which  represents  the  organic  residues  most  resistant  to  decay 
and  which  consequently  has  accumulated  in  the  soil  during  the  past  centuries. 
The  decay  of  this  old  humus  can  be  hastened  both  by  tillage,  which  maintains 
a porous  condition  and  thus  permits  the  oxygen  of  the  air  to  enter  the  soil  more 
freely  and  to  effect  the  more  rapid  oxidation  of  the  organic  matter,  and  also  by 
incorporating  with  the  old,  resistant  residues  some  fresh  organic  matter,  such 
as  farm  manure,  clover  roots,  etc.,  which  decay  rapidly  and  thus  furnish  or  lib- 
erate organic  matter  and  inorganic  food  for  bacteria,  the  bacteria,  under  such 
favorable  conditions,  appearing  to  have  power  to  attack  and  decompose  the  old 
humus.  It  is  probably  for  this  reason  that  peat,  a very  inactive  and  inefficient 
fertilizer  when  used  by  itself,  becomes  much  more  effective  when  composted  with 
fresh  farm  manure ; so  that  two  tons  of  the  compost1  may  be  worth  as  much  as 
two  tons  of  manure,  but  if  applied  separately,  the  peat  has  little  value.  Bac- 
terial action  is  also  promoted  by  the  presence  of  limestone. 

The  condition  of  the  organic  matter  of  the  soil  is  indicated  more  or  less 
definitely  by  the  ratio  of  carbon  to  nitrogen.  As  an  average,  the  fresh  organic 

1In  his  book,  “Fertilizers,”  published  in  1839,  Cuthbert  W.  Johnson  reported  such  com- 
post to  have  been  much  used  in  England  and  to  be  valued  as  highly,  ‘ ‘ weight  for  weight,  as 
farm-yard  dung.” 


1915] 


McLean  County 


43 


matter  incorporated  with  soils  contains  about  twenty  times  as  much  carbon  as 
nitrogen,  but  the  carbohydrates  ferment  and  decompose  much  more  rapidly  than 
the  nitrogenous  matter ; and  the  old  resistant  organic  residues,  such  as  are  found 
in  normal  subsoils,  commonly  contain  only  five  or  six  times  as  much  carbon  as 
nitrogen.  Soils  of  normal  physical  composition,  such  as  loam,  clay  loam,  silt 
loam,  and  fine  sandy  loam,  when  in  good  productive  condition,  contain  about 
twelve  to  fourteen  times  as  much  carbon  as  nitrogen  in  the  surface  soil ; while 
in  old,  worn  soils  that  are  greatly  in  need  of  fresh,  active,  organic  manures,  the 
ratio  is  narrower,  sometimes  falling  below  ten  of  carbon  to  one  of  nitrogen. 
Soils  of  cut-over  or  burnt-over  timber  lands  sometimes  contain  so  much  partially 
decayed  wood  or  charcoal  as  to  destroy  the  value  of  the  nitrogen-carbon  ratio 
for  the  purpose  indicated.  (Except  in  newly  made  alluvial  soils,  the  ratio  is 
usually  narrower  in  the  subsurface  and  subsoil  than  in  the  surface  stratum.) 

It  should  be  kept  in  mind  that  crops  are  not  made  out  of  nothing.  They 
are  composed  of  ten  different  elements  of  plant  food,  every  one  of  which  is 
absolutely  essential  for  the  growth  and  formation  of  every  agricultural  plant. 
Of  these  ten  elements  of  plant  food,  only  two  (carbon  and  oxygen)  are  secured 
from  the  air  by  all  agricultural  plants,  only  one  (hydrogen)  from  water,  and 
seven  from  the  soil.  Nitrogen,  one  of  these  seven  elements  secured  from  the 
soil  by  all  plants,  may  also  be  secured  from  the  air  by  one  class  of  plants 
(legumes),  in  case  the  amount  liberated  from  the  soil  is  insufficient;  but  even 
these  plants  (which  include  only  the  clovers,  peas,  beans,  and  vetches,  among 
our  common  agricultural  plants)  secure  from  the  soil  alone  six  elements  (phos- 
phorus, potassium,  magnesium,  calcium,  iron,  and  sulfur),  and  also  utilize  the 
soil  nitrogen  so  far  as  it  becomes  soluble  and  available  during  their  period  of 
growth. 

Plants  are  made  of  plant-food  elements  in  just  the  same  sense  that  a build- 
ing is  made  of  wood  and  iron,  brick,  stone,  and  mortar.  Without  materials, 
nothing  material  can  be  made.  The  normal  temperature,  sunshine,  rainfall,  and 
length  of  season  in  central  Illinois  are  sufficient  to  produce  50  bushels  of  wheat 
per  acre,  100  bushels  of  corn,  100  bushels  of  oats,  and  4 tons  of  clover  hay ; and, 
where  the  land  is  properly  drained  and  properly  tilled,  such  crops  would  fre- 
quently be  secured  if  the  plant  foods  were  present  in  sufficient  amounts  and 
liberated  at  a sufficiently  rapid  rate  to  meet  the  absolute  needs  of  the  crops. 

Crop  Requirements 

The  accompanying  table  shows  the  requirements  of  wheat,  corn,  oats,  and 
clover  for  the  five  most  important  plant-food  elements  which  the  soil  must  fur- 
nish. (Iron  and  sulfur  are  supplied  normally  in  sufficient  abundance  compared 
with  the  amounts  needed  by  plants,  so  that  they  are  never  known  to  limit  the 
yield  of  general  farm  crops  grown  under  normal  conditions.) 

To  be  sure,  these  are  large  yields,  but  shall  we  try  to  make  possible  the 
production  of  yields  only  half  or  a quarter  as  large  as  these,  or  shall  we  set  as 
our  ideal  this  higher  mark,  and  then  approach  it  as  nearly  as  possible  with 
profit?  Among  the  four  crops,  corn  is  the  largest,  with  a total  yield  of  more 
than  six  tons  per  acre;  and  yet  the  100-bushel  crop  of  corn  is  often  produced 
on  rich  pieces  of  land  in  good  seasons.  In  very  practical  and  profitable  systems 


44 


Soil  Report  No.  10 


[May, 


Table  A. — Plant  Pood  in  Wheat,  Corn,  Oats,  and  Clover 


Produce 

Nitro- 

Phos- 

Potas- 

Magne- 

Cal- 

Kind 

Amount 

gen 

phorus 

sium 

sium 

cium 

lbs. 

lbs. 

lbs. 

lbs. 

lbs. 

Wheat,  grain 

50  bu. 

71 

12 

13 

4 

1 

Wheat  straw 

2%  tons 

25 

4 

45 

4 

10 

Corn,  grain 

100  bu. 

100 

17 

19 

7 

1 

Corn  stover 

3 tons 

48 

6 

52 

10 

21 

Corn  cobs 

% ton 

2 

2 

Oats,  grain 

100  bu. 

66 

11 

16 

4 

2 

Oat  straw 

2%  tons 

31 

5 

52 

7 

15 

Clover  seed 

4bu. 

7 

2 

3 

1 

1 

Clover  hay 

4 tons 

160 

20 

120 

31 

117 

Total  in  grain  and  seed 

2441 

42 

51 

16 

4 

Total  in  four  crops.  . 

5101 

77 

322 

68 

168 

3These  amounts  include  the  nitrogen  contained  in  the  clover  seed  or  hay,  which,  how- 
ever, may  be  secured  from  the  air. 


of  farming,  the  Illinois  Experiment  Station  has  produced,  as  an  average  of  the 
six  years  1905  to  1910,  a yield  of  87  bushels  of  corn  per  acre  in  grain  farming 
(with  limestone  and  phosphorus  applied,  and  with  crop  residues  and  legume 
crops  turned  under),  and  90  bushels  per  acre  in  live-stock  farming  (with  lime- 
stone, phosphorus,  and  manure) . 

The  importance  of  maintaining  a rich  surface  soil  cannot  be  too  strongly 
emphasized.  This  is  well  illustrated  by  data  from  the  Rothamsted  Experiment 
Station,  the  oldest  in  the  world.  On  Broadbalk  field,  where  wheat  has  been 
grown  since  1844,  the  average  yields  for  the  ten  years  1892  to  1901  were  12.3 
bushels  per  acre  on  Plot  3 (unfertilized)  and  31.8  bushels  on  Plot  7 (well  ferti- 
lized), but  the  amounts  of  both  nitrogen  and  phosphorus  in  the  subsoil  (9  to  27 
inches)  were  distinctly  greater  in  Plot  3 than  in  Plot  7,  thus  showing  that  the 
higher  yields  from  Plot  7 were  due  to  the  fact  that  the  plowed  soil  had  been 
enriched.  In  1893  Plot  7 contained  per  acre  in  the  surface  soil  (0  to  9 inches) 
about  600  pounds  more  nitrogen  and  900  pounds  more  phosphorus  than  Plot  3. 
Even  a rich  subsoil  has  little  value  if  it  lies  beneath  a worn-out  surface. 

Methods  of  Liberating  Plant  Food 

Limestone  and  decaying  organic  matter  are  the  principal  materials  which 
the  farmer  can  utilize  most  profitably  to  bring  about  the  liberation  of  plant 
food.  The  limestone  corrects  the  acidity  of  the  soil  and  thus  encourages  the 
development  not  only  of  the  nitrogen-gathering  bacteria  which  live  in  the  nodules 
on  the  roots  of  clover,  cowpeas,  and  other  legumes,  but  also  the  nitrifying 
bacteria,  which  have  power  to  transform  the  insoluble  and  unavailable  organic 
nitrogen  into  soluble  and  available  nitrate  nitrogen.  At  the  same  time,  the 
products  of  this  decomposition  have  power  to  dissolve  the  minerals  contained 
in  the  soil,  such  as  potassium  and  magnesium,  and  also  to  dissolve  the  insoluble 
phosphate  and  limestone  which  may  be  applied  in  low-priced  forms. 

Tillage,  or  cultivation,  also  hastens  the  liberation  of  plant  food  by  permit- 
ting the  air  to  enter  the  soil  and  burn  out  the  organic  matter;  but  it  should 
never  be  forgotten  that  tillage  is  wholly  destructive,  that  it  adds  nothing  what- 


.1915  J 


McLean  County 


45 


ever  to  the  soil,  but  always  leaves  it  poorer.  Tillage  should  be  practiced  so 
far  as  is  necessary  to  prepare  a suitable  seed  bed  for  root  development  and 
also  for  the  purpose  of  killing  weeds,  but  more  than  this  is  unnecessary  and 
unprofitable  in  seasons  of  normal  rainfall ; and  it  is  much  better  actually  to 
enrich  the  soil  by  proper  applications  or  additions,  including  limestone  and 
organic  matter  (both  of  which  have  power  to  improve  the  physical  condition 
as  well  as  to  liberate  plant  food)  than  merely  to  hasten  soil  depletion  by  means 
of  excessive  cultivation. 


Permanent  Soil  Improvement 

The  best  and  most  profitable  methods  for  the  permanent  improvement  of 
the  common  soils  of  Illinois  are  as  follows: 

(1)  If  the  soil  is  acid,  apply  at  least  two  tons  per  acre  of  ground  lime- 
stone, preferably  at  times  magnesian  limestone  (CaC03MgC03) , which  con- 
tains both  calcium  and  magnesium  and  has  slightly  greater  power  to  correct 
soil  acidity,  ton  for  ton,  than  the  ordinary  calcium  limestone  (CaC03) ; and 
continue  to  apply  about  two  tons  per  acre  of  ground  limestone  every  four  or 
five  years.  On  strongly  acid  soils,  or  on  land  being  prepared  for  alfalfa,  five 
tons  per  acre  of  ground  limestone  may  well  be  used  for  the  first  application. 

(2)  Adopt  a good  rotation  of  crops,  including  a liberal  use  of  legumes,  and 
increase  the  organic  matter  of  the  soil  either  by  plowing  under  the  legume  crops 
and  other  crop  residues  (straw  and  corn  stalks),  or  by  using  for  feed  and  bed- 
ding practically  all  the  crops  raised  and  returning  the  manure  to  the  land  with 
the  least  possible  loss.  No  one  can  say  in  advance  what  will  prove  to  be  the 
best  rotation  of  crops,  because  of  variation  in  farms  and  farmers,  and  in  prices 
for  produce,  but  the  following  are  suggested  to  serve  as  models  or  outlines: 

First  year,  corn. 

Second  year,  corn. 

Third  year,  wheat  or  oats  (with  clover  or  clover  and  grass). 

Fourth  year,  clover  or  clover  and  grass. 

Fifth  year,  wheat  and  clover  or  grass  and  clover. 

Sixth  year,  clover  or  clover  and  grass. 

Of  course  there  should  be  as  many  fields  as  there  are  years  in  the  rotation. 
In  grain  farming,  with  small  grain  grown  the  third  and  fifth  years,  most  of  the 
coarse  products  should  be  returned  to  the  soil,  and  the  clover  may  be  clipped 
and  left  on  the  land  (only  the  clover  seed  being  sold  the  fourth  and  sixth  years)  ; 
or,  in  live-stock  farming,  the  field  may  be  used  three  years  for  timothy  and 
clover  pasture  and  meadow  if  desired.  The  system  may  be  reduced  to  a five- 
year  rotation  by  cutting  out  either  the  second  or  the  sixth  year,  and  to  a four- 
year  system  by  omitting  the  fifth  and  sixth  years. 

With  two  years  of  corn,  followed  by  oats  with  clover-seeding  the  third  year, 
and  by  clover  the  fourth  year,  all  produce  can  be  used  for  feed  and  bedding  if 
other  land  is  available  for  permanent  pasture.  Alfalfa  may  be  grown  on  a fifth 
field  for  four  or  eight  years,  which  is  to  be  alternated  with  one  of  the  four ; or 
the  alfalfa  may  be  moved  every  five  years,  and  thus  rotated  over  all  five  fields 
every  twenty-five  years. 

Other  four-year  rotations  more  suitable  for  grain  farming  are : 

Wheat  (and  clover),  corn,  oats,  and  clover;  or  corn  (and  clover),  cowpeas,  wheat,  and 
clover.  (Alfalfa  may  be  grown  on  a fifth  field  and  rotated  every  five  years,  the 
hay  being  sold.) 


Soil  Report  No.  10 


[May, 


46 

Good  th  ree-year  rotations  are: 

Corn,  oats,  and  clover;  corn,  wheat,  and  clover;  or  wheat  (and  clover),  corn  (and 
clover),  and  cowpeas,  in  which  two  cover  crops  and  one  regular  crop  of  legumes 
are  grown  in  three  years. 

A five-year  rotation  of  (1)  corn  (and  clover),  (2)  cowpeas,  (3)  wheat, 
(4)  clover,  and  (5)  wheat  (and  clover)  allows  legumes  to  be  seeded  four  times. 
Alfalfa  may  be  grown  on  a sixth  field  for  five  or  six  years  in  the  combination, 
rotation,  alternating  between  two  fields  every  five  years,  or  rotating  over  all  the 
fields  if  moved  every  six  years. 

To  avoid  clover  sickness  it  may  sometimes  be  necessary  to  substitute  sweet 
clover  or  alsike  for  red  clover  in  about  every  third  rotation,  and  at  the  same 
time  to  discontinue  its  use  in  the  cover-crop  mixture.  If  the  corn  crop  is  not 
too  rank,  cowpeas  or  soybeans  may  also  be  used  as  a cover  crop  (seeded  at  the 
last  cultivation)  in  the  southern  part  of  the  state,  and,  if  necessary  to  avoid 
disease,  these  may  well  alternate  in  successive  rotations. 

For  easy  figuring  it  may  well  be  kept  in  mind  that  the  following  amounts 
of  nitrogen  are  required  for  the  produce  named: 

1 bushel  of  oats  (grain  and  straw)  requires  1 pound  of  nitrogen. 

1 bushel  of  corn  (grain  and  stalks)  requires  1%  pounds  of  nitrogen. 

1 bushel  of  wheat  (grain  and  straw)  requires  2 pounds  of  nitrogen. 

1 ton  of  timothy  requires  24  pounds  of  nitrogen. 

1 ton  of  clover  contains  40  pounds  of  nitrogen. 

1 ton  of  cowpeas  contains  43  pounds  of  nitrogen. 

1 ton  of  average  manure  contains  10  pounds  of  nitrogen. 

The  roots  of  clover  contain  about  half  as  much  nitrogen  as  the  tops,  and 
the  roots  of  cowpeas  contain  about  one-tenth  as  much  as  the  tops. 

Soils  of  moderate  productive  power  will  furnish  as  much  nitrogen  to  clover 
(and  two  or  three  times  as  much  to  cowpeas)  as  will  be  left  in  the  roots  and 
stubble.  In  grain  crops,  such  as  wheat,  corn,  and  oats,  about  two-thirds  of  the 
nitrogen  is  contained  in  the  grain  and  one-third  in  the  straw  or  stalks.  (See 
also  discussion  of  “The  Potassium  Problem,”  on  pages  following.) 

(3)  On  all  lands  deficient  in  phosphorus  (except  on  those  susceptible  to 
serious  erosion  by  surface  washing  or  gullying)  apply  that  element  in  consid- 
erably larger  amounts  than  are  required  to  meet  the  actual  needs  of  the  crops 
desired  to  be  produced.  The  abundant  information  thus  far  secured  shows  posi- 
tively that  fine-ground  natural  rock  phosphate  can  be  used  successfully  and  very 
profitably,  and  clearly  indicates  that  this  material  will  be  the  most  economical 
form  of  phosphorus  to  use  in  all  ordinary  systems  of  permanent,  profitable  soil 
improvement.  The  first  application  may  well  be  one  ton  per  acre,  and  subse- 
quently about  one-half  ton  per  acre  every  four  or  five  years  should  be  applied, 
at  least  until  the  phosphorus  content  of  the  plowed  soil  reaches  2,000  pounds  per 
acre,  which  may  require  a total  application  of  from  three  to  five  or  six  tons  per 
acre  of  raw  phosphate  containing  121/2  percent  of  the  element  phosphorus. 

Steamed  bone  meal  and  even  acid  phosphate  may  be  used  in  emergencies, 
but  it  should  always  be  kept  in  mind  that  phosphorus  delivered  in  Illinois  costs 
about  3 cents  a pound  in  raw  phosphate  (direct  from  the  mine  in  carload  lots), 
but  10  cents  a pound  in  steamed  bone  meal,  and  about  12  cents  a pound  in  acid 
phosphate,  both  of  which  cost  too  much  per  ton  to  permit  their  common  purchase 
by  farmers  in  carload  lots,  which  is  not  the  case  with  limestone  or  raw  phos- 
phate- 


1915 ] 


McLean  County 


47 


Phosphorus  once  applied  to  the  soil  remains  in  it  until  removed  in  crops, 
unless  carried  away  mechanically  by  soil  erosion.  (The  loss  by  leaching  is  only 
about  li/2  pounds  per  acre  per  annum,  so  that  more  than  150  years  would  be 
required  to  leach  away  the  phosphorus  applied  in  one  ton  of  raw  phosphate.) 

The  phosphate  and  limestone  may  be  applied  at  any  time  during  the  rota- 
tion, but  a good  method  is  to  apply  the  limestone  after  plowing  and  work  it  into 
the  surface  soil  in  preparing  the  seed  bed  for  wheat,  oats,  rye,  or  barley,  where 
clover  is  to  be  seeded ; while  phosphate  is  best  plowed  under  with  farm  manure, 
clover,  or  other  green  manures,  which  serve  to  liberate  the  phosphorus. 

(4)  Until  the  supply  of  decaying  organic  matter  has  been  made  adequate, 
on  the  poorer  types  of  upland  timber  and  gray  prairie  soils  some  temporary 
benefit  may  be  derived  from  the  use  of  a soluble  salt  or  a mixture  of  salts,  such 
as  kainit,  which  contains  both  potassium  and  magnesium  in  soluble  form  and 
also  some  common  salt  (sodium  chlorid).  About  600  pounds  per  acre  of  kainit 
applied  and  turned  under  with  the  raw  phosphate  will  help  to  dissolve  the  phos- 
phorus as  well  as  to  furnish  available  potassium  and  magnesium,  and  for  a few 
years  such  use  of  kainit  may  be  profitable  on  lands  deficient  in  organic  matter, 
but  the  evidence  thus  far  secured  indicates  that  its  use  is  not  absolutely  necessary 
and  that  it  will  not  be  profitable  after  adequate  provision  is  made  for  supplying 
decaying  organic  matter,  since  this  will  necessitate  returning  to  the  soil  the 
potassium  contained  in  the  crop  residues  from  grain  farming  or  the  manure 
produced  in  live-stock  farming,  and  will  also  provide  for  the  liberating  of  potas- 
sium from  the  soil.  (Where  hay  or  straw  is  sold,  manure  should  be  bought.) 

On  soils  which  are  subject  to  surface  washing,  including  especially  the 
yellow  silt  loam  of  the  upland  timber  area,  and  to  some  extent  the  yellow-gray 
silt  loam  and  other  more  rolling  areas,  the  supply  of  minerals  in  the  subsurface 
and  subsoil  (which  gradually  renew  the  surface  soil)  tends  to  provide  for  a 
low-grade  system  of  permanent  agriculture  if  some  use  is  made  of  legume  plants, 
as  in  long  rotations  with  much  pasture,  because  both  the  minerals  and  nitrogen 
are  thus  provided  in  some  amount  almost  permanently;  but  where  such  lands 
are  farmed  under  such  a system,  not  more  than  two  or  three  grain  crops  should 
be  grown  during  a period  of  ten  or  twelve  years,  the  land  being  kept  in  pasture 
most  of  the  time;  and  where  the  soil  is  acid  a liberal  use  of  limestone,  as  top- 
dressings  if  necessary,  and  occasional  reseeding  with  clovers  will  benefit  both  the 
pasture  and  indirectly  the  grain  crops. 

Advantage  of  Crop  Rotation  and  Permanent  Systems 

It  should  be  noted  that  clover  is  not  likely  to  be  well  infected  with  the 
clover  bacteria  during  the  first  rotation  on  a given  farm  or  field  where  it  has 
not  been  grown  before  within  recent  years ; but  even  a partial  stand  of  clover 
the  first  time  will  probably  provide  a thousand  times  as  many  bacteria  for  the 
next  clover  crop  as  one  could  afford  to  apply  in  artificial  inoculation,  for  a single 
root-tubercle  may  contain  a million  bacteria  developed  from  one  during  the  sea- 
son’s growth. 

This  is  only  one  of  several  advantages  of  the  second  course  of  the  rotation 
over  the  first  course.  Thus  the  mere  practice  of  crop  rotation  is  an  advantage, 
especially  in  helping  to  rid  the  land  of  insects  and  foul  grass  and  weeds.  The 
clover  crop  is  an  advantage  to  subsequent  crops  because  of  its  deep-rooting  char- 


48 


Soil  Report  No.  10 


L May, 


actcristic.  The  larger  applications  of  organic  manures  (made  possible  by  the 
larger  crops)  are  a great  advantage ; and  in  systems  of  permanent  soil  improve- 
ment, such  as  are  here  advised  and  illustrated,  more  limestone  and  more  phos- 
phorus are  provided  than  are  needed  for  the  meager  or  moderate  crops  pro- 
duced during  the  first  rotation,  and  consequently  the  crops  in  the  second  rota- 
tion have  the  advantage  of  such  accumulated  residues  (well  incorporated  with 
the  plowed  soil)  in  addition  to  the  regular  applications  made  during  the  second 
rotation. 

Tli  is  means  that  these  systems  tend  positively  toward  the  making  of  richer 
lands.  The  ultimate  analyses  recorded  in  the  tables  give  the  absolute  invoice 
of  these  Illinois  soils.  They  show  that  most  of  them  are  positively  deficient  only 
in  limestone,  phosphorus,  and  nitrogenous  organic  matter ; and  the  accumulated 
information  from  careful  and  long-continued  investigations  in  different  parts  of 
the  United  States  clearly  establishes  the  fact  that  in  general  farming  these  essen- 
tials can  be  supplied  with  greatest  economy  and  profit  by  the  use  of  ground  nat- 
ural limestone,  very  finely  ground  natural  rock  phosphate,  and  legume  crops  to 
be  plowed  under  directly  or  in  farm  manure.  On  normal  soils  no  other  applica- 
tions are  absolutely  necessary,  but,  as  already  explained,  the  addition  of  some 
soluble  salt  in  the  beginning  of  a system  of  improvement  on  some  of  these  soils 
produces  temporary  benefit,  and  if  some  inexpensive  salt,  such  as  kainit,  is  used, 
it  may  produce  sufficient  increase  to  more  than  pay  the  added  cost. 

The  Potassium  Problem 

As  reported  in  Illinois  Bulletin  123,  where  wheat  has  been  grown  every  year 
for  more  than  half  a century  at  Rothamsted,  England,  exactly  the  same  increase 
was  produced  (5.6  bushels  per  acre),  as  an  average  of  the  first  24  years,  whether 
potassium,  magnesium,  or  sodium  was  applied,  the  rate  of  application  per  annum 
being  200  pounds  of  potassium  sulfate  and  molecular  equivalents  of  magnesium 
sulfate  and  sodium  sulfate.  As  an  average  of  60  years  (1852  to  1911),  the  yield 
of  wheat  was  12.7  bushels  on  untreated  land  and  23.3  bushels  where  86  pounds 
of  nitrogen  and  29  pounds  of  phosphorus  per  acre  per  annum  were  applied. 
As  further  additions,  85  pounds  of  potassium  raised  the  yield  to  31.3  bushels; 
52  pounds  of  magnesium  raised  it  to  29.2  bushels ; and  50  pounds  of  sodium  raised 
it  to  29.5  bushels.  Where  potassium  was  applied,  the  wheat  crop  removed  an- 
nually an  average  of  40  pounds  of  that  element  in  the  grain  and  straw,  or  three 
times  as  much  as  would  be  removed  in  the  grain  only  for  such  crops  as  are 
suggested  in  Table  A.  The  Rothamsted  soil  contained  an  abundance  of  lime- 
stone, but  no  organic  matter  was  provided  except  the  little  in  the  stubble  and 
roots  of  the  wheat  plants. 

On  another  field  at  Rothamsted  the  average  yield  of  barley  for  60  years 
(1852  to  1911)  was  14.2  bushels  on  untreated  land,  38.1  bushels  where  43  pounds 
of  nitrogen  and  29  pounds  of  phosphorus  were  applied  per  acre  per  annum; 
while  the  further  addition  of  85  pounds  of  potassium,  19  pounds  of  magnesium, 
and  14  pounds  of  sodium  (all  in  sulfates)  raised  the  average  yield  to  41.5 
bushels.  Where  only  70  pounds  of  sodium  were  applied  in  addition  to  the 
nitrogen  and  phosphorus,  the  average  was  43.0  bushels.  Thus,  as  an  average 
of  60  years,  the  use  of  sodium  produced  1.8  bushels  less  wheat  and  1.5  bushels 


1915 ] 


McLean  County 


49 


more  barley  than  the  use  of  potassium,  with  both  grain  and  straw  removed  and 
no  organic  manures  returned. 

In  recent  years  the  effect  of  potassium  is  becoming  much  more  marked  than 
that  of  sodium  or  magnesium,  on  the  wheat  crop ; but  this  must  be  expected  to 
occur  in  time  where  no  potassium  is  returned  in  straw  or  manure,  and  no  pro- 
vision made  for  liberating  potassium  from  the  supply  still  remaining  in  the  soil. 
If  the  wheat  straw,  which  contains  more  than  three-fourths  of  the  potassium 
removed  in  the  wheat  crop  (see  Table  A),  were  returned  to  the  soil,  the  neces- 
sity of  purchasing  potassium  in  a good  system  of  farming  on  such  land  would 
be  at  least  very  remote,  for  the  supply  would  be  adequately  maintained  by 
the  actual  amount  returned  in  the  straw,  together  with  the  additional  amount 
which  would  be  liberated  from  the  soil  by  the  action  of  decomposition  products. 

While  about  half  the  potassium,  nitrogen,  and  organic  matter,  and  about 
one-fourth  the  phosphorus  contained  in  manure  is  lost  by  three  or  four  months’ 
exposure  in  the  ordinary  pile  in  the  barn  yard,  there  is  practically  no  loss 
if  plenty  of  absorbent  bedding  is  used  on  cement  floors,  and  if  the  manure  is 
hauled  to  the  field  and  spread  within  a day  or  two  after  it  is  produced.  Again, 
while  in  average  live-stock  farming  the  animals  destroy  two-thirds  ‘of  the  or- 
ganic matter  and  retain  one-fourth  of  the  nitrogen  and  phosphorus  from  the 
food  they  consume,  they  retain  less  than  one-tenth  of  the  potassium ; so  that  the 
actual  loss  of  potassium  in  the  products  sold  from  the  farm,  either  in  grain 
farming  or  in  live-stock  farming,  is  wholly  negligible  on  land  containing  25,000 
pounds  or  more  of  potassium  in  the  surface  6%  inches. 

The  removal  of  one  inch  of  soil  per  century  by  surface  washing  (which  is 
likely  to  occur  wherever  there  is  satisfactory  surface  drainage  and  frequent  cul- 
tivation) will  permanently  maintain  the  potassium  in  grain  farming  by  re- 
newal from  the  subsoil,  provided  one-third  of  the  potassium  is  removed  by  crop- 
ping before  the  soil  is  carried  away. 

From  all  these  facts  it  will  be  seen  that  the  potassium  problem  is  not  one 
of  addition  but  of  liberation ; and  the  Rothamsted  records  show  that  for  many 
years  other  soluble  salts  have  practically  the  same  power  as  potassium  to  increase 
crop  yields  ill  the  absence  of  sufficient  decaying  organic  matter.  Whether  this 
action  relates  to  supplying  or  liberating  potassium  for  its  own  sake,  or  to  the 
power  of  the  soluble  salt  to  increase  the  availability  of  phosphorus  or  other  ele- 
ments, is  not  known,  but  where  much  potassium  is  removed,  as  in  the  entire  crops 
at  Rothamsted,  with  no  return  of  organic  residues,  probably  the  soluble  salt 
functions  in  both  ways. 

As  an  average  of  112  separate  tests  conducted  in  1907,  1908,  1909,  and  1910 
on  the  Fairfield  experiment  field,  an  application  of  200  pounds  of  potassium 
sulfate,  containing  85  pounds  of  potassium  and  costing  $5.10,  increased  the  yield 
of  corn  by  9.3  bushels  per  acre ; while  600  pounds  of  kainit,  containing  only  60 
pounds  of  potassium  and  costing  $4,  gave  an  increase  of  10.7  bushels.  Thus,  at 
40  cents  a bushel  for  corn,  the  kainit  paid  for  itself ; but  these  results,  like  those 
at  Rothamsted,  were  secured  where  no  adequate  provision  had  been  made  for 
decaying  organic  matter. 

Additional  experiments  at  Fairfield  included  an  equally  complete  test  with 
potassium  sulfate  and  kainit  on  land  to  which  8 tons  per  acre  of  farm  manure 


50 


Soil  Report  No.  10 


[May, 


were  applied.  As  an  average  of  112  tests  with  each  material,  the  200  pounds 
of  potassium  sulfate  increased  the  yield  of  corn  by  1.7  bushels,  while  the  600 
poundc  of  kainit  also  gave  an  increase  of  1.7  bushels.  Thus,  where  organic 
manure  was  supplied,  very  little  effect  was  produced  by  the  addition  of  either1 
potassium  sulfate  or  kainit ; in  part  perhaps  because  the  potassium  removed  in 
the  crops  is  mostly  returned  in  the  manure  if  properly  cared  for,  and  perhaps 
in  larger  part  because  the  decaying  organic  matter  helps  to  liberate  and  hold 
in  solution  other  plant-food  elements,  especially  phosphorus. 

In  laboratory  experiments  at  the  Illinois  Experiment  Station,  it  has  been 
shown  by  chemical  analysis  that  potassium  salts  and  most  other  soluble  salts 
increase  the  solubility  of  the  phosphorus  in  soil  and  in  rock  phosphate;  also 
that  the  addition  of  glucose  with  rock  phosphate  in  pot-culture  experiments 
increases  the  availability  of  the  phosphorus,  as  measured  by  plant  growth,  altho 
the  glucose  consists  only  of  carbon,  hydrogen,  and  oxygen,  and  thus  contains 
no  plant  food  of  value. 

If  we  remember  that,  as  an  average,  live  stock  destroy  two-thirds  of  the  or- 
ganic matter  of  the  food  they  consume,  it  it  easy  to  determine  from  Table  A that 
more  organic  matter  will  be  supplied  in  a proper  grain  system  than  in  a strictly 
live-stock  system ; and  the  evidence  thus  far  secured  from  older  experiments  at 
the  University  and  at  other  places  in  the  state  indicates  that  if  the  corn  stalks, 
straw,  clover,  etc.,  are  incorporated  with  the  soil  as  soon  as  practicable  after  they 
are  produced  (which  can  usually  be  done  in  the  late  fall  or  early  spring),  there 
is  little  or  no  difficulty  in  securing  sufficient  decomposition  in  our  humid  climate 
to  avoid  serious  interference  with  the  capillary  movement  of  the  soil  moisture, 
a common  danger  from  plowing  under  too  much  coarse  manure  of  any  kind  in 
the  late  spring  of  a dry  year. 

If,  however,  the  entire  produce  of  the  land  is  sold  from  the  farm,  as  in  hay 
farming  or  when  both  grain  and  straw  are  sold,  of  course  the  draft  on  potas- 
sium will  then  be  so  great  that  in  time  it  must  be  renewed  by  some  sort  of  appli- 
cation. As  a rule,  farmers  following  this  practice  ought  to  secure  manure  from 
town,  since  they  furnish  the  bulk  of  the  material  out  of  which  manure  is  pro- 
duced. 

Calcium  and  Magnesium 

When  measured  by  the  actual  crop  requirements  for  plant  food,  magnesium 
and  calcium  are  more  limited  in  some  Illinois  soils  than  potassium.  But  with 
these  elements  we  must  also  consider  the  loss  by  leaching.  As  an  average  of  90 
analyses1  of  Illinois  well-waters  drawn  chiefly  from  glacial  sands,  gravels,  or  till, 
3 million  pounds  of  water  (about  the  average  annual  drainage  per  acre  for 
Illinois)  contained  11  pounds  of  potassium,  130  of  magnesium,  and  330  of  cal- 
cium. These  figures  are  very  significant,  and  it  may  be  stated  that  if  the  plowed 
soil  is  well  supplied  with  the  carbonates  of  magnesium  and  calcium,  then  a very 
considerable  proportion  of  these  amounts  will  be  leached  from  that  stratum. 
Thus  the  loss  of  calcium  from  the  plowed  soil  of  an  acre  at  Rothamsted,  England, 
where  the  soil  contains  plenty  of  limestone,  has  averaged  more  than  300  pounds 
a year  as  determined  by  analyzing  the  soil  in  1865  and  again  in  1905.  Prac- 
tically 'the  same  amount  of  calcium  was  found,  by  analyses,  in  the  Rothamsted 
drainage  waters. 

‘Reported  by  Doctor  Bartow  and  associates,  of  the  Illinois  State  Water  Survey. 


1915 ] 


McLean  County 


51 


Common  limestone,  which  is  calcium  carbonate  (CaC03),  contains,  when 
pure,  40  percent  of  calcium,  so  that  800  pounds  of  limestone  are  equivalent  to 
i 320  poupds  of  calcium.  Where  10  tons  per  acre  of  ground  limestone  were 
K applied  at  Edgewood,  Illinois,  the  average  annual  loss  during  the  next  ten  years 
amounted  to  790  pounds  per  acre.  The  definite  data  from  careful  investigations 
seem  to  be  ample  to  justify  the  conclusion  that  where  limestone  is  needed  at 
least  2 tons  per  acre  should  be  applied  every  4 or  5 years. 

It  is  of  interest  to  note  that  thirty  crops  of  clover  of  four  tons  each  would 
require  3,510  pounds  of  calcium,  while  the  most  common  prairie  land  of  southern 
Illinois  contains  only  3,420  pounds  of  total  calcium  in  the  plowed  soil  of  an 
acre.  (See  Soil  Report  No.  1.)  Thus  limestone  has  a positive  value  on  some 
soils  for  the  plant  food  which  it  supplies,  in  addition  to  its  value  in  correcting 
soil  acidity  and  in  improving  the  physical  condition  of  the  soil.  Ordinary  lime- 
stone (abundant  in  the  southern  and  western  parts  of  the  state)  contains  nearly 
800  pounds  of  calcium  per  ton;  while  a good  grade  of  dolomitic  limestone  (the 
’ more  common  limestone  of  northern  Illinois)  contains  about  400  pounds  of  cal- 
I cium  and  300  pounds  of  magnesium  per  ton.  Both  of  these  elements  are  fur- 
| nished  in  readily  available  form  in  ground  dolomitic  limestone. 


In  the  management  of  most  soil  types,  one  very  important  thing,  aside  from 
proper  fertilization,  tillage,  and  drainage,  is  to  keep  the  soil  in  good  physical 
condition,  or  good  tilth.  The  constituent  most  important  for  this  purpose  is 
organic  matter.  Not  only  does  it  impart  good  tilth  to  the  soil,  but  it  prevents 
I much  loss  by  washing  on  rolling  land,  warms  the  soil  by  absorption  of  heat,  re- 

I tains  moisture  during  drouth  and  prevents  the  soil  from  running  together  badly ; 
and,  as  it  decays,  it  furnishes  nitrogen  for  the  crop  and  aids  in  the  liberation  of 
mineral  plant  food.  This  constituent  must  be  supplied  to  the  soil  in  every  prac- 
tical way,  so  that  the  amount  may  be  maintained  or  even  increased.  It  is  being 
broken  down  during  a large  part  of  the  year,  and  th^  nitrates  produced  are  used 
for  plant  growth.  This  decomposition  is  necessary,  but  it  is  also  quite  necessary 
that  the  supply  be  maintained. 

The  physical  effect  of  organic  matter  in  the  soil  is  to  produce  a granulation, 
or  mellowness,  very  favorable  for  tillage  and  the  development  of  plant  roots.  If 
continuous  cropping  takes  place,  accompanied  with  the  removal  or  the  destruc- 
tion of  the  corn  stalks  and  straw,  the  amount  of  organic  matter  is  gradually 
diminished  and  a condition  of  poor  tilth  will  ultimately  follow.  In  many  cases 
this  already  limits  the  crop  yields.  The  remedy  is  to  increase  the  organic-matter 
content  by  plowing  under  manure  or  crop  residues,  such  as  corn  stalks,  straw, 
and  clover.  Selling  these  products  from  the  farm,  burning  them,  or  feeding 
them  and  not  returning  the  manure,  or  allowing  a very  large  part  of  the  manure 
to  be  lost  before  it  is  returned  to  the  land,  all  represent  bad  practice. 

One  of  the  chief  sources  of  loss  of  organic  matter  in  the  corn  belt  is  the 
practice  of  burning  the  corn  stalks.  Could  the  farmers  be  made  to  realize  how 
great  a loss  this  entails,  they  would  certainly  discontinue  the  practice.  Probably 
1 no  form  of  organic  matter  acts  more  beneficially  in  producing  good  tilth  than 
corn  stalks.  It  is  true  that  they  decay  rather  slowly,  but  it  is  also  true  that  their 


Physical  Improvement  of  Soils 


Soil  Report  No.  10 


[ Man  r 


52 

durability  in  the  soil  after  partial  decomposition  is  exactly  what  is  needed  in 
the  maintenance  of  an  adequate  supply  of  humus. 

The  nitrogen  in  a ton  of  corn  stalks  is  iy2  times  that  in  a ton  of  manure,  and 
a ton  of  dry  corn  stalks  incorporated  with  the  soil  will  ultimately  furnish  as 
much  humus  as  4 tons  of  average  farm  manure;  but  when  burned,  both  the 
humus-making  material  and  the  nitrogen  which  these  stalks  contain  are  de- 
stroyed and  lost  to  the  soil. 

The  objection  is  often  raised  that  when  stalks  are  plowed  under  they  inter- 
fere very  seriously  in  the  cultivation  of  corn,  and  thus  indirectly  destroy  a great 
deal  of  corn.  If  corn  stalks  are  well  cut  up  and  then  turned  under  to  a depth 
of  5^2  to  6 inches  when  the  ground  is  plowed  in  the  spring,  very  little  trouble 
will  result. 

Where  corn  follows  corn,  the  stalks,  if  not  needed  for  feeding  purposes, 
should  be  thoroly  cut  up  with  a sharp  disk  or  stalk  cutter  and  turned  under. 
Likewise,  the  straw  should  be  returned  to  the  land  in  some  practical  way,  either 
directly  or  as  manure.  Clover  should  be  one  of  the  crops  grown  in  the  rotation, 
and  it  should  be  plowed  under  directly  or  as  manure  instead  of  being  sold  as  hay, 
except  when  manure  can  be  brought  back. 

It  must  be  remembered,  however,  that  in  the  feeding  of  hay,  or  straw,  or 
corn  stalks,  a great  destruction  of  organic  matter  takes  place,  so  that  even  if  the 
fresh  manure  were  returned  to  the  soil,  there  would  still  be  a loss  of  50  to  70 
percent  owing  to  the  destruction  of  organic  matter  by  the  animal.  If  manure  is 
allowed  to  lie  in  the  farmyard  for  a few  weeks  or  months,  there  is  an  additional 
loss  which  amounts  to  from  one-third  to  two-thirds  of  the  manure  recovered 
from  the  animal.  This  is  well  shown  by  the  results  of  an  experiment  conducted 
by  the  Maryland  Experiment  Station,  where  80  tons  of  manure  were  allowed  to 
lie  for  a year  in  the  farmyard  and  at  the  end  of  that  time  but  27  tons  remained, 
entailing  a loss  of  about  66  percent  of  the  manure.  Most  of  this  loss  occurs 
within  the  first  three  or  four  months,  when  fermentation,  or  ‘ ‘ heating,  ’ ’ is  most 
active.  Two  tons  of  manure  were  exposed  from  April  29  to  August  29,  by  the 
Canadian  Experiment  Station  at  Ottawa.  During  these  four  months  the  organic 
matter  was  reduced  from  1,938  pounds  to  655  pounds.  To  obtain  the  greatest 
value  from  the  manure,  it  should  be  applied  to  the  soil  as  soon  as  possible  after 
it  is  produced. 

It  is  a common  practice  in  the  corn  belt  to  pasture  the  corn  stalks  during 
the  winter  and  often  rather  late  in  the  spring  after  the  frost  is  out  of  the 
ground.  This  tramping  of  stock  sometimes  puts  the  soil  in  bad  condition  for 
working.  It  becomes  partially  puddled  and  will  be  cloddy  as  a result.  If 
tramped  too  late  in  the  spring,  the  natural  agencies  of  freezing  and  thawing, 
and  wetting  and  drying,  with  the  aid  of  ordinary  tillage,  fail  to  produce  good 
tilth  before  the  crop  is  to  be  planted.  Whether  the  crop  is  corn  or  oats,  it  neces- 
sarily suffers,  and  if  the  season  is  dry,  much  damage  may  result.  If  the  field  is 
put  in  corn,  a poor  stand  is  likely  to  follow,  and  if  put  in  oats,  a compact  soil  is 
formed  which  is  unfavorable  for  their  growth.  Sometimes  the  soil  is  worked 
when  too  wet.  This  also  produces  a partial  puddling  which  is  unfavorable  to 
physical,  chemical,  and  biological  processes.  The  bad  effect  will  be  greater  if 
cropping  has  reduced  the  organic  matter  below  the  amount  necessary  to  maintain 
good  tilth. 


